So I understand why that includes Layzner and OG Macross, but if you just wanted Gundam then why did you say this game was "heavily influenced" by Nadesico, Aquarion, and Grendizer? I mean, all three of those have completely ridiculous mecha (Daimajin/Denjin/Tetsujin in the former, literally everything in the latter two) who would be over the line in any scenario given the limits you've placed. You also mentioned that's it's founded on SRWOG, which is a setting that started ridiculous (black hole engines among other things) and only got sillier and went harder on the power creep as time went on. If you wanted Gundam, why didn't you just say you wanted Gundams to begin with? Just saying, it would probably help you avoid misunderstandings like this.
There's very little in the way of "misunderstanding". There was an evolution from a more general mecha concept to a more solidified setting based upon what has occurred and what characters, and machines, were presented. That evolution lead to a more grounded, real robot feel to the game rather than a more ridiculous tone. SRWOG is useful as a reference for the game's
tone, not necessarily its tech. Which, frankly, is wildly inconsistent with itself to begin with. Its origin is a crossover series where mechs of wildly different types and powers could be on a somewhat level playing field, and the inconsistency shows to this day.
You made your assessment based upon an earlier phase. It was clarified. No one else has had this 'misunderstanding'. Indeed, it's less of a misunderstanding than it is the result of irritation due to assumptions being contradicted.
So you're actively planning on adding power creep?
Well, it's your game I suppose.
Anyway, if Zeta is the limit, doesn't that bring Haros and the Learning Computer from original Mobile Suit Gundam (though the Haro also appeared in Zeta) into play? I mean, we could just say mine has a last-gen, more robotic type, the gmpc you're bringing in has a next-gen, more human type? That way yours is still special and impressive and I get to do my thing in the corner. Sound okay to you?
Furthermore you mention combiners aren't in play, but the Core Block System and G-Parts/G-Fighter of the original RX-78 Gundam were pretty much the same concept. I mean, assuming when you say "combiner" you're referring to a mecha formed from component machines like Getter Robo or Combattler V, rather than something like ChoRyuJin or Big Rayearth.
I don't even know where to begin.
For one thing, this isn't the Gundam universe. Zeta is a helpful baseline for where mecha technology is. That doesn't mean "it was in Zeta, I can have it" because then I'd simply use the G-Valkyrie to Waverider Crash every opponent with the power of Newtype magic. Or I'd use funnels to wreck every opponent without moving. I could keep going, but I don't think I need to. Zeta is helpful as a
general guideline for where technology is. If you want to see where technology
specifically is, take a look at the actual machines that have been approved for the game. Or ask, if there's something you haven't seen.
A combining mecha, on the other hand, is absolutely machines along the lines of ChoRyuJin. Yes, machines like Dancouga, Grendizer and such also count. They are one specific subset of what "combiner" encompasses. Machines like ChoRyuJin, Gurren Lagann, GaoGaiGar, or combiners from Transformers are another. No one in their right mind would call the Core Block System or the G-Armor/G-Parts a combiner. The CBS is a glorified escape pod and is treated as such in all subsequent sequels, prequels, and retellings of the One Year War. The G-Armor and G-Parts were more traditional super-robot-esque elements that Tomino was mandated to include because Sunrise felt it would help market 0079 to kids. Hence, these elements are downplayed if not removed for followups to 0079 including the MSG movie trilogy. They didn't fit Tomino's vision and were included reluctantly. A better Gundam example would be Zeta's Super Gundam (Mk. II plus G-Defenser) or the ZZ Gundam, both of which
were combiners of different sorts. For an AU look, if that's your preference, look at the 00 Gundam and the ) Raiser.
Getting to the main point, though, you don't get to try and move the goalposts to say "a Zeta baseline means Haros, so I can have my robot buddy". The Learning Computer, additionally, is another one of the elements significantly downplayed in every subsequent iteration of the Gundam franchise because it didn't fit.
@Crimmy stated that robot buddies would not presently be a thing, as AI may play into future plot points, and that
should be the end of it. Your tone feels less like attempting to determine whether or not your ideas fit with the universe and more like figuring out how to reshape the universe to fit
your vision.
If that's not your intent, perhaps you should reevaluate how you come across.
Lastly, "upgrades" and "introducing new elements" does not necessarily mean "power creep". Increasing tech levels and midseason upgrades are par for the course in many mecha anime, video games, and inspired RPGs. Such is the intent here.