I'd say maybe lean into savage worlds, if only because OG deadlands is a product of its time, being influenced by white wolf games whichs means there's most likely gonna be some wonky math and it's going to be overly precious over its metaplot and NPCS tied to it. Plus, game design trends have like evolved over the years so there's gonna be stuff that's just kinda outmoded.
Not to say savage world is perfect, as it has its flaws and quirks. I don't if they resolved in like whatever edition they're currently using, but it involves combat, damage, and benny flow. Savage worlds has a pronounced death spiral, every time you get wounded you acquire more and more penalties to rolls and depending on how bad the hit is you can gain multiple in one go.
On one hand high level antagonists in a fight can be annoying to fight as they will either evade your hit or tank damage. So you can have rounds that are like whiff-fests or just chipping away at the enemy and slowly stacking those penalties until the fights easier and or via bennies or natural luck a player gets that one good hit that turns the table.
And when you do that it's pretty gratifying to finally crack that tough shell and lay into them. And it makes sense in terms of being a way to model exhaustion and getting too tired/hurt to keep fighting well. Which works for settings where the characters aren't like superheroes or it's like an action movie where the protags should be mowing through dudes until they meet the antagonist or one of the heavies.
But on the receiving end it can be painful and frustrating if you're the guy who's blessed by poor luck. Especially when fighting like a boss or mid-boss type as their numbers will be high enough that if you take even a moderately bad hit in the beginning not only are you that much closer to getting ko'd, it's only going to be more difficult to participate as you'll get worse on defense and offense. And also each penalty makes it that much easier to get a crit since it's based on reaching a certain difference between the two rolls.
Bennies besides letting you influence the story with them as a player have a bunch of combat utility to them. The pertinent ones being rerolls, negating wounds, and breaking the shaken status. They keep combat manageable, but the issue is GMs being stingy and running out. Cuz while you have like certain guidelines of what would earn a benny, ultimately it falls to the GM. And going without them for a bit can feel bad, as it just turns into a slog. Also the GM gets their own bennies, and it's fun to do Yu-gi-oh reverse trap card stuff with being spent to counter each other. So keep them flowing and you should be fine.
I haven't played OG Deadlands and it's been while since I read the rules so like I don't remember how durable characters feel there. Also, my experience was with explorer's edition and I got no clue what's the current version being used for the game line. So maybe the characters are a little less brittle when benniless in combat.
Wow, that was a lot, but a good read. I've since begun reading the Savage Worlds version, and they're currently in "adventure" edition, whatever that means.
I see what you mean with some of the combat, but having learned both, I agree that Savage Worlds is the better way to go. The entire game is radically simplified, reducing the dice pools and making the damage system much easier to follow (Classic you actually not only had to worry about being shaken or winded, you had to track wound levels on hit locations rather than a set limit overall). The initiative is much improved, reducing the number of cards drawn. the overwhelming majority of npc's and enemies have much more limited mechanics and abilities, so while other games run on the assumption of exceptionalism for player characters, the mechanics in this game really seem to reflect that.
Much of the game design seems to have been geared towards simplification, so it's more approachable for new players (and provides a simpler alternative for fans of Pathfinder and Rifts, both of which enjoy a presence in Savage Worlds titles separate from their original forms), but especially making it approachable as a new GM as well. "very little book keeping" I think is a term I've heard thrown around.
Regarding the Bennies? the stinginess is either a problem of previous versions, or a gm specific issue, because the material I'm reading encourages being generous with them, specifically because players are encouraged to use them liberally as well, simply for the fact that unspent Bennies don't roll over to the next session. It's strictly "Use 'em or lose 'em."
The death spiral... Yeah, that can be a problem, I listened to a game that was played over soembodies twitch stream or whatever, and by the end, in the only combat session they had for that session, 1 of maybe 3 players died, and died for good (death doesn't necessarily mean the end of your character in the setting, as it's possible to come back as undead, referred to as "Harrowed"). Most npc's are always rolling fewer dice, don't have the use of Bennies, and only take 1 wound to be incapacitated (which isn't even strictly dead), but with "Wild Cards" (either player characters or npc's meant to be on a similar power level) can only take 3, it only takes a few good rolls to go down.
That being said... It also takes a player not utilizing their superior abilities and resources, as well as considering withdrawing from an encounter, as well as a GM that takes an adversarial stance against their players? Because when I run games, my aim isn't to coddle my players, but I'm not out to get them, either. It's possible to have bad things happening to the players be possible, without looking for opportunities to make them sorry they showed up to the session. Like, I can get an npc villain having the leg up on player characters, but hoarding Bennies to use them against players? That's not a power gap, or an inherant flaw in the mechanics; your Marshal is just a dick.