Now, this was originally a no brainer for me, but the more thought I put into it, doubly so with the environment not being a strict duel type scenario, the more interesting things got. This will showcase the format I have planned for each person, covering strengths, weaknesses, and situation wise how squaring off with each other person will go. Since, you know, the easiest way to compare power is to have them squaring off with each other.

STRENGTHS
-Astartes Physiology-
At their most basic, your typical Space Marine is superior in mind and body compared to other members of the Imperium. I won't go into fine detail about every major point of a Marine's creation process, but it does make them rather intimidating and difficult to take down foes, and that's without taking into account their typical wargear. But, in short, their resilience to most conventional methods of inflicting damage are vastly amplified, as is their ability to quickly recover from said wounds, and spit poison. Because that is a thing folks seem to forget at times.

-Wargear-
Nergüi is specifically noted to be wearing a slightly modified version of the Mk. 6 Corvus pattern Astartes Power Armor. This is already a model that is lighter than other suits of Astartes grade Power Armor, without sacrificing durability from what I can tell, as well as improving power efficiency in regards to the suit, auto senses, and lends itself better to stealth compared to other Marks of armor. Add in the Diagnoster Helm, and Nergüi probably as the sharpest ability to pick out anything unclear from his surroundings. His weapons are a bit more conventional, the bolt pistol being standard fare, but of note are both his power sabre, granting him another means of besting any armor the rest of the compared characters are wearing, and his Reductor. While it may not necessarily be meant for combat, in a pinch, it would grant Nergüi the means to punch through any armor being worn by the rest of the characters, being designed to get through his brother's power armor AND Ossmodula enhanced rib cage, which is noted for being a solid interlocking bone plates that are bullet proof.

-Experience & Deathwatch Training-
Probably the hardest thing to directly quantify as a solid number, but by far the most important. White Scars are fast attack experts, meaning that Nergüi would be no different and thanks to his light weight armor, would be able to move deceptively fast for his size and get into range of where he would be most effective, which in my opinion is in hand to hand. Considering the rest of his gear, a bolt pistol is rather lack luster in comparison (Though highly effective in its own right). Having served in the Third War for Armageddon, faced chaos renegades, done spooky work in the Deathwatch, means he probably has more combined experience than the rest of the party, potentially combined. The Deathwatch would also have equipped him for handling most conventional Xenos threats and, as needed, more esoteric ones.

WEAKNESSES
-Lack of Range-
As I mentioned in wargear and training, Nergüi has a rather alarming lack of options to reach out beyond melee range and fight. A bolt pistol, and two grenades (one of which designed for anti tank use). While Astartes pattern grenades produce greater yields than conventional ones, Nergüi really only has a one off chance of getting a kill or flushing his target out with a grenade. A lot of the strategy that the rest of the contenders would have to use would be keeping out of reach of his melee weapons.

-Prodigious Size-
Compared to the rest of the party, a Space Marine stands out. Hard. While this is somewhat mitigated by the Corvus armor's affinity for stealth, possibly thanks to the Raven Guard doing a lot of the initial trial work for it, he stands out and is a larger target than everyone else. While this still leaves the problem of getting through the power armor itself, being larger means being easier to hit, speaking generally.

COMPARISONS
As a side note, for these, I am not sticking to the power pattern listed, but the order of how the Character Sheets were submitted.

-Celestian Andromedai Morgenstern-
She'll be giving Nergüi the most potent straight up fight once they find each other, and Nergüi will be well served to force her into melee as soon as possible. Considering she fields a modified Bolter designed for accurate ranged operations, and an automatic masterkey style attachment (which is more negligable due to both wearing Power Armor), Nergüi would stand an increasing chance of defeat should he remain outside of hand to hand. Even in the melee, a chainsword is a respectable melee weapon and will create an interesting duel once melee is engaged. Of special note here is the fact Andromedai bears a Rosarius, meaning it will render any initial attempts to breach the field with attacks null and void. They can be overloaded, and Nergüi power sabre would be able to do this, but it only reinforces the fact he has to get in close.

-Grenadier Ansgar Staudinger-
The biggest problem will be digging him out of wherever he chooses to bunker down, considering his extremely defensive approach to this matchup. The second biggest will be the sheer amount of explosives being lobbed in his direction, including anti tank and his modified demolition charges. Nergüi however can wound and kill the Krieger with anything in his kit, even the bolt pistol, though Krieg Grenadier Carapace is noted for being made of plasteel with ceramite reinforcement, making him tankier for slower movement results. Melee is laughable, due to both the problems of reach and lack of any effective means of reliably injuring Nergüi on the part of the Krieger. Ansgar's Type XIV (Heavy), a Hellgun, would be able to get through the joints with focused fire, but its doubtful that Ansgar would have the time to be able to put enough fire into the joints to cripple Nergüi before being forced into melee and slaughtered.

-Vala Sal Felere-
This matchup can boil down to who shoots first, putting it bluntly. If Vala can get a clean line of sight on Nergüi long enough to draw a bead with her custom las sniper which, considering it draws power from Las Cannon cells, is likely more powerful in armor penetration due to its design, she could likely put him down in one well placed shot. Of course, the rest of her weapons stand little to no chance of getting through his armor, let alone in a timely manner, so if he gets close enough to force her las sniper to no longer be an effective choice, he has the edge. Considering Vala's salvaged power armor, which will see the same problems that Sororitas armor does when compared to Astartes armor, won't be providing enough protection to stop anything in Nergüi's kit, barring the bolt pistol to a degree.

-Arbitrator Herold Altega-
He's screwed.

Jokes aside, Herold is going to have an extremely, extremely hard time doing anything to Nergüi. While his shield will protect him in melee (for a short time) and from range, the only means he has to actually wound Nergüi would be with a power maul. Unfortunately, it is specifically noted that Herold has a Shock Maul, not a power maul. The difference being, shock mauls lack a power field which can be adjusted to levels that could knock down walls, since true to their name, shock mauls use electrical discharge to incapacitate their targets. Lacking any tools to really wound, let alone incapacitate or kill Nergüi, the odds of Herold being able to actually do anything are astronomic at best.

-Psyker Adrianne Valenthin-
The only member of the party who would likely be able to find her foe faster than Nergüi due to her servoskulls and divination, Adrianne also has plenty of means of wounding and even killing Nergüi. However, every manifestation of her powers seen takes a considerable bit of time, in terms of combat, to actually manifest which would give the Deathwatch Apothocarian time to react. Coupled with her nasty habit for theatrics and walking out to flaunt her powers could just get her in trouble. Gunning her down is unlikely though, due to Adrianne's refractor field. Forcing her into a melee would be Nergüi's best and most efficient chance here, where the focus and time to manifest more potent powers would be unlikely to avail themselves, and his power sabre would be able to match her, albeit two handed, power sabre in a duel scenario.

I have been seriously torn as to where to put Adrianne, for a variety of factors. Originally she was going to be far lower, but her psyker powers force her to be higher. She is one of the more situational characters, honestly, in regards to scenarios in how both people meet in combat, but I'll cover her strengths and weaknesses, plus pairings, same as before. Her attitude made it really hard to place her as high as I have, but in the matchups I'll cover how that would be a problem.

STRENGTHS
-Psyker-
Most of her powers are drawn from the Schools of Divination and Telekinesis. This makes getting the drop on her extremely difficult, and her ability to manipulate and maneuver the battlefield second to none. However, lacking offensive powers outside of a listed Smite and Storm of Lightning, and the fact she lacks any sort of self enhancing powers or healing means that injuries that occur are going to stay and will impact her ability to fight long term. Also notable is that the elaborate or flashy, such as her VORTEX OF DOOM also typically have low level Perils events, and are fairly uncontrollable once unleashed. On at least one occasion that I can remember, her survival of such events came down to dumb luck.

-Combat Experience-
Having been assigned to both Guard and Arbites units has given Adrianne a fairly wide base of experience, though certain events do make this less applicable than one might anticipate. Most of her assistance was passive, using Divination powers to assist her allies being the most notable, though her survival of Mordran V did change her rather drastically. Having survived being a Psyker in this day and age does give her an edge, though compared to some, her experience in combat isn't as robust, it isn't anything to be discounted.

-Wargear-
Being one of the characters not wearing Power Armor, her armor is also a custom job using Armaplas, making it equivalent to Carapace armor. More notable is her two handed power sabre, which is rather curious that it isn't a force weapon by technical definition, though how it reads almost treats it like one. For this case, it will lack the ability to instakill anything it wounds, but retain its destructive ability. Her use of a Plasma Pistol as a sidearm, though it seems to have a copious lack of use anywhere else, does give her a means of defeating armored targets.

WEAKNESSES
-Suicidal Behavior-
After Mordran V, her reckless use of warp powers and general attitude does not lend itself well to a fight, doubly so considering how most of the other characters operate in a fight. The showing off and openly flagrant disregard for restraint would create a rather glaring opening for most others to abuse should they know how to. While her Refractor Field might mitigate this to a degree, concentrated volume or strength of fire could bring it down, and considering the amount of unarmored areas that are exposed, being flagrant and open with her actions is unwise indeed.

-Armor Coverage-
Looking over what is covered by Adrianne's armor, there are a number of glaring issues once the Refractor Field fails. Considering it isn't a full set of Carapace armor, which can be considered equivalent due to the mentioned armaplas construction, well placed volumes of fire could cripple her and make her ability to maneuver vastly lowered, as well as explosive weapons being far more effective. Notable is that her Refractor Field also isn't on at all times, assumed since it is specifically mentioned whenever it is on how it looks. If she were to somehow miss her foe, a well placed shot could kill her before she had a chance to react.

COMPARISONS

-Celestian Andromedai Morgenstern-
Adrianne would have the edge in finding Andromedai, due to both divination and servoskull surveillance (This is going to be a common running trend). When it comes down to an actual fight, both characters have means of nullifying incoming weapons fire, Refractor Field and Rosarius respectively. It is noted that Refractors are less reliable than Rosarius units, though bolter fire is less destructive than plasma fire. Speaking of, the only weapons that could pose a serious threat to the Celestian while her Rosarius is active would be Psyker powers and the power sabre, amplified by telekinetic energy as it is. Of course, this means either having the presence of mind to not expose herself more than her power use would until she struck with something that could pierce the Rosarius, which is limited, or could engage Andromedai in melee, a dubious exercise as well due to the proper Power Armor and the fact a Chainsword can work through carapace grade armor as fast as a power weapon can power armor.

-Grenadier Ansgar Staudinger-
One of the characters that would be in immediate danger from the plasma pistol, though her seemingly typical lack of ever seeming to remember it exists would work in his favor, his best bet would be to, unsurprisingly, let Adrianne come to him. Volume of fire from his Hellgun, or demolition charges, would have to be used to bring down her Refractor Field, after which, actually getting through her actual armor would be easier than one might think. Problems occur in the fact that, as a Telekinetic psyker, any thrown explosives could, in theory, be caught and returned to sender if thrown without cooking the explosive. Melee is as laughable as ever, doubly so since, with Adrianne being a foot and a half taller and using a two handed power sabre, Ansgar would have no means to protect himself from a power weapon nor would he even be able to reach her without being cut down. If she chose to try and channel a power to strike him with, given his extensive experience with handling Chaos and the Warp, he would likely not give her the chance to finish if he could help it, meaning judicious explosive and Hellgun fire to interrupt.

-Vala Sal Felere-
Vala's tactics against Adrianne would have to rely on her being able to bring down her Refractor with custom las sniper and employ her other weapons to breach weak points in her defenses before Adrianne could bring any of her weapons or powers to bear. Adrianne would only need to get in one good hit to really make Vala hurt, as everything combat ready in Adrianne's kit would be able to damage power armor (Barring her ceremonial dagger, which is going to be frankly forgotten for the most part here). The most troubling thing that Adrianne would have against Vala would, again, be Divination and Servo-Skulls, making ambushing her extremely difficult and making her odds of success against Adrianne in the proposed scenario rather low.

-Arbitrator Herold Altega-
Still Screwed.

I don't promise to stop making that joke. Another case of his crippling lack of range or anything that could seriously disrupt a Refractor Field means that he really is just screwed. Adrianne could stand out in the open, let her field soak Shotgun fire, and unleash warp spawned powers on the poor Arbites while, should a melee fight occur, his odds are slightly, slightly better. Again, the sheer difference in reach and the fact that a Shock Maul lacks the ability to really get through the Refractor field, though if the field was down a strike to an unarmored area could have some rather effective results, but that relies on her either not having her field up, or somehow not have brought Herold down before repeated Shock Maul strikes eventually shorted out the Field. Seriously, Herold, why a Shock Maul?

-Apothecary Nergüi 'Boraunegen'-
As a first instance, most of the rematch thoughts on each character facing off covers more how Adrianne, or the others, could win instead of covering the most practical outcome. In this case, its not too difficult a situation for Adrianne to handle Nergüi, the Apothecary only just edging out ahead of Adrianne in my opinion in terms of power. A Vortex, or any of her albeit limited offensive powers could do some real damage to his Power Armor, while her Refractor Field would soak up any bolt pistol fire while he closed the gap. Once in melee, she could potentially land a destructive enough blow to cripple Nergüi, though she is actually better off remembering she has a Plasma Pistol and not getting into a melee fight with the Deathwatch Apothecary.

Ahh, the fearless bolter bitch leader of our band of Inquisitorial agents. Given she has a more reliable method of shrugging off attacks, she would be higher if not for her rather lack luster kit and mostly typical approach to battle. Notable for being the only person to carry a Melta bomb, brave for that. Not terribly useful fighting the other characters outside some shenanigans filled situation, but hey, bonus points.

STRENGTHS
-Celestian of the Sisters of Battle-
Celestians are veterans and have seen more than their fair share of trouble and combat, and tend to be better in a melee than your average Bolter Bitch Sister. She probably has the second most diverse range of enemies faced in terms of conventional military service, Nergüi being above due to his Deathwatch service and whatever happened there. This puts her up in terms of experience as well, though overall experience in terms of second place compared to Nergüi is a tie, depending on how on wants to quantify such things.

-Strategist-
As noted in her personality, Andromedai typically always has a plan, and this is a powerful thing that cannot be discounted. Knowing what your getting into, and how you plan to already handle it, is good indeed. Its better to also be flexible, which is noted as something worth mentioning during her personality. Being able to plan for and lead a group as diverse as this one also gives her some bonus points, considering how close they are going to be at points to killing each other.

-Wargear-
The biggest thing here is that damned Rosarius. Seriously, that is what is going to nullify most of her oppositions means of bringing her down before she can do the same to them. Otherwise, nothing too special to note here. Her Bolter is typical pattern for Adeptus Sororitas with some modification focused on ranged performance, and an automatic masterkey Seriously, an automatic shotgun attachment, where does the ammo feed go that lets it get more than two to four shots off without making it unwieldy and bulky to a fault?. Power armor is typical of the Sisters as well, the key difference being her lack of the Black Carapace, meaning she doesn't get a strength advantage from it as much as Nergüi would, being a Space Marine. No, that isn't a -4 Str joke, its just the case of a lack of Black Carapace. Oh, and her explosives are rather focused on anti tank, which limits their use against the other people in this case. Going to make some tankers very unhappy though.

WEAKNESSES
I have this feeling Andromedai was created to act as much as a middle ground to compensate for others extremes as she was to be a solid character, so picking out weaknesses is actually a bit tricky. However, a bit tricky is a far cry from impossible, so allow me to nitpick.

-Jill of all Trades-
Her lack of really specializing equipment pretty much means that she isn't going to be beating the others in their own fields of expertise. If she finds herself trying to best them at their own games, she is going to lose more often than she will succeed. Having her near the middle of the list sort of fits this, since it is her main glaring weakness. She isn't a specialist, she won't outperform a specialist, but she can cover for their deficiencies as needed. This means she will have to be focused on not only knowing what her enemy is good at, but what she will have to do to either mitigate or outright nullify that advantage completely.

COMPARISONS

-Grenadier Ansgar Staudinger-
FUCKING ROSARIUS FIELD

Ahem, do pardon me and let us continue. Ansgar's only practical option for breaking down Andromedai's Rosarius would be an unrealistic amount of volume of fire from his Hellgun, to the point that Andromedai might as well be pitying him and just letting him put shots into it until one of their tools breaks first. Its unlikely that, should she see it coming, that a demolition charge, the only other options Ansgar has to get through that Rosarius field, would land more than a glancing hit, even with him having modified them to be usable as impromptu lobbed explosives. Otherwise, she could choose to either gun him down at range, being one of the cases where her modified Bolter would be of effective use, or approach and cut him to ribbons since, again, his melee options are laughable at best currently.

-Vala Sal Felere-
The combination of power armor and Rosarius field is going to cripple any chances Vala has to seriously get through Andromedai's defenses, even with her modified las sniper weapon. On the other hand, Andromedai would likely be best served getting into melee with Vala, though she could likely take her out from a distance with her bolter without too much trouble. This highlights the problem of quantifying Vala's custom scavenged armor built from Imperial power armor, but I'm putting it between proper Power Armor and Carapace in terms of effectiveness. As such, considering Bolters can kill those wearing proper Power Armor, the scavanged and customized version Vala has on wouldn't protect her long enough to be able to get through the Rosarius Field.

-Arbitrator Herold Altega-
Should be at in a hardware store, with how screwed he's been.

Not Sorry. I sort of feel like a broken record here, and seriously feel bad about it, but Herold's crippling lack of weapons that can get through protective fields or power armor for that matter makes these matchups rather horribly one sided. His odds are better in melee than the other two so far, thanks to his shield and Andromedai's lack of a power weapon in this case, but it would only be a stalling tactic before she landed a solid blow or just wore down his shield/shield arm. Once again, why a Shock Maul? A Power Maul would have made these odds so much better for poor ol' Herold here.

-Psyker Adrianne Valenthin-
The battle of the protective fields, which would make their fight take quite awhile.

Refractors are less reliable, but the most potent ranged weapon that could be effectively employed by Andromedai is her Bolter, while her superior Rosarius could, in theory, be taking plasma shots instead. What really makes this matchup fall out of favor is the Psyker powers and inability to reliably avoid detection by Adrianne. Coupled with the power sabre should melee ensue, the gap in raw power actually settles this out of favor. Andromedai's best chances in this case would be to keep her distance and wear down the Refractor Field, since once its down, the Bolter would make rather quick work of Adrianne's otherwise less than stellar defenses.

-Apotehcary Nergüi 'Boraunegen'-

While Nergüi lacks a protective field, he pretty much trumps Andromedai in most other catagories. Experience, strength and resilience, wargear outside the Rosarius. Andromedai's best odds are, once again, to try and not get caught in close quarters with Nergüi and use her modified Bolter to bring him down before he can get close. Easier said than done, considering that she would likely be caught out before being able to get in enough effective fire to kill off the Apothecary.

I'll be honest, I am extremely hesitant to even rate my character at all due to the personal bias I hold, but I'll do what I can to rate him speaking evenly.

STRENGTHS
-Death Korp Grenadier, Former Death Korp Engineer-
Ansgar has been literally bred, born, raised, and trained to be a soldier, thanks to the rather unique environment of Krieg. This gives him a deceptively large pool of experience to draw from for someone of his age, and has lived through things that, by all rights, no Guardsmen has any right to have survived. This also gives him a rather varied base for tactics and tricks, considering the wide skill base the two jobs within the Death Korp require, and considering the trench fighting nature of the Kriegers, means he is rather vicious in hand to hand. If only his melee weapons weren't completely outclassed by the majority of those used by the rest of the party that have been mentioned thus far.

-Lucky or Blessed-
A man bred and raised to die for the Emperor, sent into constant battles with his regiment that lead to near total annihilation of his regiment, and he keeps surviving. Whether this is an unnatural level of luck, or the fact that a certain someone is watching out for him from on high, no one can deny the fact that he really, really shouldn't be alive right now. This is probably the hardest to give hard numbers for, but cannot be discounted. Seriously, no Krieger should be alive after what he's been through, and I'll openly acknowledge that. Whether its a good thing or not in the long term, its debatable, but in terms of combat, cannot be discounted readily.

-Wargear-
Death Korp Grenadier Carapace utilizes a mixture of Plasteel and Ceramite, meaning that while it is extremely durable, it will slow him down in comparison. This actually will make him the slowest moving, due to the weight of his kit, compared to everyone else, though more durable for it. His Type XIV (Heavy) is a Krieg issue version of the Hellgun, with the typical traits and one thing that makes his melee situation worse, its lack of bayonet lug. Most notable is his sheer volume of explosives, he might as well be the Santa Clause of explosives, carrying a bag full of Frags, Kraks, and custom Demolition charges that he can throw at things instead of planting properly as needed. His melee weapons, though, will be covered in his weaknesses.

WEAKNESSES
-Short-
Seriously, I think he is either second or first for the shortest character here. While it might make him a smaller target, more problematically, his reach in a fight is crippled because of it. This means that everyone will have a reach advantage on him, in regards to melee fighting, though this is mostly notable with those already mentioned so far. Speaking otherwise, this can affect his ability to navigate should he have to scale vertical surfaces of sufficient treachery. So, in terms of other party members, he will likely be outmaneuvered whenever it comes to vertical situations.

-Piss Poor Melee-
So he is tied for the worse melee equipment as of the writing of this comparison (And not with Herold). His Type XIV (Heavy) lacks a bayonet lug so he has no means of creating an impromptu spear, which would help his reach a bit, and his entrenching tool, while effective in his hands, lacks reach or armor penetrating qualities to handle anyone wearing anything sturdier than Flak without potentially excessive levels of work. Viciousness and skill only make up so much for lack luster equipment, and it shows where most of his failings against others come from being forced into hand to hand fighting.

COMPARISONS
-Celestian Andromedai Morgenstern-

As mentioned, Ansgar's lack of means of being able to reliably breech the Rosarius field means that he is going to have to employ dirty tricks to stand a chance. This means ambushes and demolition booby traps, since most of his fights he has to force them to come after him. Fortunately, for most cases, they are better served getting to him before he has a chance to start digging in and booby trapping his surroundings with explosives. Once the Rosarius Field is done, Ansgar still has to get through the Power Armor and survive the return fire from the Bolter or, if he is extremely unfortunate, Chainsword. The key to his survival is staying close enough to harass but not get forced into melee.

-Vala Sal Felere-

The biggest threat is, once again, her custom las sniper and is likely the only person he is going to have to go after instead of waiting for them to come to him. However, digging someone out of a position is something Ansgar is equipped for, and worse case scenario he would have the means to bring down the building that Vala is in. Otherwise, the scavanged power armor custom job Vala has would not be nearly in her favor as I initially considered, mostly due to the fact that Ansgar has experience and training in fighting power armored foes, so someone wearing an inferior set of power armor wouldn't be against him as much as the others. Her other weapons would have trouble getting through his Carapace armor, heavier than normal as it is, and she beats him for worse melee weapon so he would be well served for getting into hand to hand fighting with Vala.

-Arbitrator Herold Altega-
Not that Screwed, actually.

Ansgar sort of marks the point where the lower tier characters, in terms of power, start, so Herold has a legitimate fighting chance against the Krieger should things go in his favor. His shield and shock maul would be more effective against Ansgar, as he is the only person besides Herold NOT wearing some form of power armor/power armor derived protection (the psyker doesn't count, considering her Refractor Field). However, the sheer volume of explosives that Ansgar could employ, and his Hellgun's volume of fire, would likely outperform Herold at all other ranges. His shotgun would be ineffective, as would his sidearm, forcing him to pursue Ansgar through any traps or terrain that was set up before hand after the fight started.

-Psyker Adrianne Valenthin-

The first problem Ansgar has when fighting Adrianne will be her Refractor Field, though this is easier to solve than the rest that come up. Concentrated fire from the Hellgun could bring it down, and considering her nature, he could in theory 'Alpha Strike' her with firepower should he get the drop on her. This brings up the main problem, which is her servo skulls and Divination powers, the odds of him getting the drop on her are astronomically low at best, and things get even worse should he be forced into hand to hand combat. An entrenching tool versus a two handed power sabre wielded by someone a foot and a half taller isn't a fight, its an execution. As such, his chances revolve around being able to abuse the fact she is reckless with her powers and behavior, and possibly hide some sort of booby trap or ambush because of it.

-Apothecary Nergüi 'Boraunegen'-

Ansgar's biggest problem is, again, that ambushing anyone in Power Armor is tricky, due to their autosenses and durability. However, against the higher power foes, Ansgar's approach to handling power armor would be second most effective on Nergüi (Most effecitve on Vala). His lack of defensive fields means that he can directly apply anti tank grenades and demolition charges as he is being pursued. However, it is unlikely he will have much time to set such things up due to hwo fast Nergüi will be able to effectively pin point his location and pursue him. The lightweight Corvus armor would mean he is moving far faster than Ansgar is prepared to handle typically, and like always, melee is suicide for Ansgar.

This one was a bit of a tossup, but the more versatile kit decided it Much as I wanted to put Herold higher.

STRENGTHS
-Mercenary Engineer-
Unlike almost every other character, she has practical experience outside of the military and outside of a regimented control period. This would give her unique perspectives and abilities to improvise and plan, and she has seen her fair share of combat like the rest of the party has. Her proven ability to think and operate on the fly is probably one of her notable strengths, as is the fact that she probably has the most extensively modified set of weapons of the entire party, and likely makes her one of the most dangerous at range.

-Wargear-
This is going to take up a lot if I discussed everything in depth, but I'll make it brief as possible. Her most notable weapon, the Nova LAS Heavy Sniper, is probably her trump card. Anyone not protected by Refractor or Rosarius fields is going to be dead from a single well placed shot (the placement changes depending on the target), though its unlikely she would be able to wield it effectively in melee. Her two sidearms, while the laspistol being close to a hotshot laspistol as far as I can estimate, would be anywhere from fairly ineffective to completely useless depending on which member of the party she squared off with. The MAG Autogun is a curious item, and could prove effective against some Carapace level armor, depending on details I frankly don't have. Her armor itself gave me some issues figuring out how resilient she would be, and I placed it in a placeholder slot between true Power Armor and Carapace. The grappling hook and tool would give her unusual mobility and on the fly improvisation, but her tactics remain largely the same for whoever she faces.

WEAKNESSES
-Range Dependent-
The majority of her useful weapons are best used at mid to long range, meaning that effectively anyone in the party getting close pretty much seals her fate. Her ability to fight in hand to hand is, frankly to me at least, unknown, and while she has scavanged and custom built armor out of Imperial power armor, the sheer number of unknowns involved with it means that I cannot treat it as true power armor at the time of this analysis. This means that, should she be closed in on, she is even more worse off than anyone else in the party.

-Low Volume of Fire-
Barring her autopistol, Vala seems to prefer each round fired to have as much power as possible, at the cost of magazine size. Every one of her modified weapons boasts abnormally low ammo counts per magazine/cell, meaning that she wouldn't be able to effectively suppress anyone, meaning that every missed shot could be a glaring opening for someone to close the distance. While it isn't an issue if she brings down her target in one shot, things can get complicated in a hurry if she is facing someone with durable enough armor, or evasive enough, to take more than one shot.

COMPARISONS
I'm going to be blunt here, Vala's best chances of winning don't really change much, and her comparisons right now are mostly her best chances of winning the unfavorable matchups. Keep her distance, preferably as far as her NOVA las sniper can effectively fire, and bring them down before she is detected.

-Celestian Andromedai Morgenstern-

The biggest problem facing Vala here, like most match ups, is how she can bring down her target before they close the gap. Andromedai's Rosarius would likely be able to soak both shots from the NOVA, meaning that while Vala is reloading, Andromedai is returning fire or closing the gap. And this is assuming both shots are a hit, considering the multi round function of each full shot, it would actually be effective in overloading the shielding due to the volume. I do not think it could bring down either the Rosarius or Refractor in one shot however, meaning in both cases Vala's position is revealed and she would have to relocate and try to hit Andromedai again before her Rosarius comes back online.

-Grenadier Ansgar Staudinger-

Vala's NOVA weapon would likely bring down Ansgar in one shot, two if he was lucky due to the layered construction of his armor. This means that her best odds are to spot him and bring him down before he finds her out. Otherwise, the amount of explosives being lobbed in her direction, including demolition charges to ruin any building being used, coupled with being closed into a melee fight or range where she could not effectively bring her NOVA to bear, means that this is fairly straightforward. Bring him down before he gets within effective range of his gear, or that is that.

-Arbitrator Herold Atlega-

Much like Ansgar's case, if Herold could close the gap, he would be able to bring Vala down. However, his problems with this are far greater. While his shield would provide some protection, the carapace armor issued to Arbites is fairly standard compared to that worn by others in the party, meaning that the NOVA is certainly going to punch through it in one well placed shot. This means that he has to close the gap to shotgun range, and likely closer as the scavanged power armor worn by Vala would mitigate the buckshot's effects, and even slug. Once in melee, Vala would be hard pressed to actually be able to best or even get clear of Herold, probably even more so than with Ansgar.

-Psyker Adrianne Valenthin-

Vala's biggest problem is, unsurprisingly at this point, the fact that Adrianne is a Divination psyker as well as Telekinetic, meaning that the odds of her being able to ambush the pysker and bring down her Refractor shield, which has a very real chance of failing after only one shot and leaving Adrianne open to following shot, are fairly slim. However, considering the behaviour that Adrianne typically displays when flaunting her powers, Vala could in theory act to abuse this. Problem being that, even without using Divination, the twin servo skulls could be used to vastly expediate how fast she is pin pointed, and nothing is stopping Adrianne from approaching from a side not being observed and bring the building down with her powers. Or engage in melee where, much like the others who don't have power weapons, would be a fairly quick affair due to a lack of practical defenses against such things.

-Apothecary Nergüi 'Boraunegen'-

Vala's NOVA would be of most use to her here, punching through the Corvus armor that Nergüi wears, however, much like a broken record at this point, she has one shot to make it count. If she gets discovered first, or otherwise cannot get a good shot off on Nergüi, she would be hard pressed to be able to actually harm the Apothecary, and much like the case with the others, melee would be very much a death sentence for her, given what is known thus far.

I'm going to preface this with how bad I feel about having to rate Herold at this point. I'm a fan of the Arbites, but compared to the kit and tools of everyone else, he really is just outclassed. Not to say he isn't a strong character, but considering we are ranking each character against the others, it just happened this way.

STRENGTHS

-Arbitrator of the Law-
Herold, as far as I see him, is probably the closest thing this party has to a close assault expert. Suprression Shield, Shock Maul, shotgun, and frag make for a classic sort of approach to breaching into a room and clearing it out of conventional targets. Most of his notable deeds occur in close quarters, further reinforcing the fact that he is a strong melee combatent. Out of the three lower tier characters, I'd say he is the most dangerous in hand to hand, and if he had a proper Power Maul, he would be even more dangerous to those in the top three.

-Wargear-
Nothing fancy here, his suppression shield is sturdy, has that nasty shock trick, and provides Herold full body protection. The shock maul, again, is a sturdy, no nonsense weapon that sadly lacks the power field that could have actually made him a contender for higher up on the list, and his remaining weapons, shotgun and autopistol, are nothing fancy, but that means there is little to go wrong with them. The carapace worn by the Arbites is almost a perfect baseline for carapace armor, although this does mean that, while perfectly effective and useful, it is probably the least protective equipment on the list.

WEAKNESSES

-Piss Poor Range-
Much like Ansgar's melee situation, Herold' ranged situation is just as bad if not worse. Most shotgun's effective range operates at around 50 yards, meaning that beyond that, Herold is unable to effectively return fire. Autopistols, and pistols in general, also typically maintain a similar effective range unless specifically mentioned otherwise. As such, anyone who can maintain a safe distance has nothing to practically fear from Herold, due to his own inability to reach out that far.

-Lack of Anti Armor-
Probably more damning is Herold's relative inability to breech armor of sufficient strength. Power Armor is beyond any of his tools ability to get through, and Carapace would give him a hard time by itself as well. As such, without any practical means to break down enemy defenses in this case, it sort of forces him to the bottom of the list. Give him a Power Maul, and its a different story completely, but as of right now, the shock maul just isn't going to cut it.

COMPARISONS

I'm not going to drag Herold through the mud anymore than I already have, and feel bad for doing so. Anyone in true power armor or with a protective field, aka Nergüi, Andromedai, and Adrianne, he has no means to actually hurt. As for Ansgar, the lack of range would cripple him as he is bombared with explosives and Hellgun fire, which would tear apart his defenses before he could get within shock maul range. Vala is his best fight, since the only weapon that would reliably harm him would be the NOVA thing of hers, and it has almost as many drawbacks as it does strengths.