To add to the @Vathar 's point, alpha is not something introduced in X2. Every single XCom game, be it original ones, remakes or spiritual successors like Aftermath etc, all of them had those nasty moments when a soldier gets ambushed by 2-3 aliens who turn him into a swiss cheese the moment he enters a building or turns around a corner(“Doors and corners, kid. Doors and corners”.). This is an inherent problem of turn-based tactical games with heavily randomized map layouts and enemy placement. Readily available high survivability is a band-aid measure here: sure, it will allow a soldier to live through an ambush but it will end up making all firefights long and sluggish with bullet spongy combatants plinking at each other, slowly grinding through each other’s HP pools. It also reduces the importance of proper tactics, positioning and cover as with lots of armour and HP, all combatants can just run for it, shrugging off 1 turn worth of damage and them engaging the enemy in QCQ.
But my main gripe is not even with high HP values but with armour. Or, more to the point, armour shredding mechanics. Right from the introduction in the first FXCom, It was a very artificial and game-y mechanic, with certain arbitrary chosen weapons becoming “armour shredders” which locked them into this very specific use. This mechanic, while interesting in theory, turned armour into some sort of HP pool on top of HP pool, making combat very formalized with mandatory shredding becoming the “damage” you have to deal before you can actually deal damage. The thing is, while armour & shredding work ok for low armour levels, this mechanic scales rather badly, making shredding absolutely mandatory in mid- and late-game battles, when damaging enemy’s HP pool becomes outright impossible without dealing armour damage first with a shredding weapon.
I think amour should not be though of as a numerical value, but rather be represented by armour quality with particular damage types(be it per-weapon or per ammo type) affecting the target differently depending on it. Shredding will have to go completely with using armour-piercing damage and seeking weak points being the main way of dealing with armoured enemies.
I envision damage and armour types as follows:
~ basic damage (here and below, examples are given for ammo types if implemented and weapons, if no special ammo types will be available): FMJ ammo, assault rifles, HE warheads
~ anti-personnel damage: hollow point ammo, shotguns, frag warheads. these weapons have higher chance to cause bleeding when dealing extra damage
~ armour piercing damage: AP ammo, anti-materiel rifles, AT warheads
~ energy damage: laser & plasma weapons. these weapons have low chance to cause bleeding due to heat-induced coagulation.
I avoid discussing more exotic damage types here (such as highly advanced human or alien weapons) as those should be custom-balanced individually.
~ No armour(unarmoured human, soft alien tissue): regular damage type deals full damage, anti-personnel damage deal extra damage. Armour piercing damage deal reduced damage due to overpenetration, energy weapons deals extra damage
~ Light armour(human in a flack jacket, hardened alien tissue, durable machinery): regular damage type deals reduced damage, anti-personnel damage deal minimal damage. Armour piercing damage deal full damage, energy weapons deals full damage
~ Heavy armour(human in a powered armour suit, alien carapace, lightly armoured machinery): regular damage type deals minimal damage with reduced chance to bleed, anti-personnel damage deal no damage, Armour piercing damage deal full damage, energy weapons deals reduced damage
~ Assault armour(ironclad aliens, heavy armoured vehicles): regular damage type deals no damage, anti-personnel damage deal no damage. Armour piercing damage deal reduced damage, energy weapons deals reduced damage
~ Reflective armour(anti-plasma body armour or alien tissue): regular damage type deals extra damage due to armour crumbling and shredding the wound further, anti-personnel damage deal full damage. Armour piercing damage deal reduced damage due to overpenetration, energy weapons deals reduced damage
All of this is of course just an example, but I think you can get the idea. Armour will not be easily removable, most of the time armour type will not change during combat. Thanks to per-body part starts, there will be no need for this as enemies will not have uniform armour across the while body, instead some parts will have weaker armour types, allowing low-penetration weapons to stay relevant. On top of that, weapons will still be at least semi-useful in most situations outside of fringe cases(attacking heavily armoured vehicles with a shotgun etc will of course be futile) as they usually can deal some damage even to the armoured parts yet will have a distinctive “area of expertise” where they will shine.
Of course, such damage mechanics work best with diverse ammo types when, just like in the original XCom, you will be able carry, say AP and HE ammo for your minigun and change it depending on the enemy you are facing.
I think this is spot-on. FXCom felt much more like a squad-based RPG in terms of how important individual soldiers were and while this approach has it’s merits in a more story-driven game(I’d love to see an Icewind Dale in XCom universe), for a proper XCom game we have to have a certain level of, not so much of a disposability per se, but the game’s expectancy that we can lose our veteran soldiers and this will not be the end of the campaign. In that sense, having class/perk-based progression is the worst possible case as this makes high-levelled soldiers extremely important for the mission’s success. If, using FXCom as an example, you physically cannot recruit a rookie and give him a sniper rifle or a minigun, despite how strong he is or how good of a shot he is, having a levelled up soldiers becomes detrimental to campaign progress. If, however, each soldier would be gradually learning the appropriate skills, getting better and better at something instead of miraculously becoming a sniper after reaching a particular level, losing ranked-up soldiers will not be as critical as it will only reduce the performance of the squad instead of completely
crippling it. But of course, such design will have to be paired with a steady stream of available recruits as if soldiers themselves are scarce, losing one of them will be a problem in and of itself, regardless of his skill level.