Actually, per system resources(points, whatever..) + long term statuses(for curses and large abnormalities - say lost limb) that can be cured only by some specific and costly means, sound like something that can give some tactical depth without crippling game-play(IMHO of-course!).
Just as example:
if character state is represented by 3 systems with level-triggered effects, that come and go immediately when amount of % change:
- movement(muscle and bones) (<50% slowed, <30% accuracy of attack go down as well,<15% unable to move, <5% unable to perform ANY action)
go down from damage: crushing damage, partially by slashing damage
go down from using impulse-type physical special moves/abilities
being affected by equipment overweight, excessive going without rest
slow regen-over-time unless <5%(critical state)
- circulation(blood circulation,breathing)(<60% hampers speech-related skills/abilities, <40% starts to take slow continuous damage-over-time, <20% continuous damage to mental system, 0% DEAD)
go down from damage: piercing(regular), gases/atmospheric effect(when cannot breath),partial slashing,partial fire
go down from using continuous-type physical special abilities (unnaturally fast movement,stealth)
being affected by equipment overweight
fast regen-over-time unless <40%(significant bleeding etc)
- mental(both brain and all neural network)(<50% accuracy of attacks go down, <30% hampers speech-related and mental/spell-related skills/abilities, <15% unconscious, 0% DEAD )
go down from damage: electrical, direct magical(or mental), sound
go down from using concentration-type(active searching, intimidation, taunt, mind control ) and spell abilities/skills
being affected by excessive going without rest
fast regen-over-time unless dead
If one have to think which type of defenses/armor are most valuable in current party and per person, that will affect his strategy not only tactics.
Also having to worry about longterm effect like level-drain or disease, that can affect interaction with NPCs or spread within party, will force people to balance party carefully(which i think is good thing).
In my opinion its better then having per limb damage, since it would require enormous amount of pause-input for big party.
Something like this also provides means to control difficulty by disabling/lowering some of levels.