How about if both fatigue and health changed significantly? I'm thinking sort of the way the UFO games did health (they didn't have fatigue though). Not a single bar of health, but a bar with some areas, typically colored or shaded, in them. For health, something like:
* Temporary Damage. Heals itself over normal time without rest. Could be a stun, knockout, or a shock effect. But if you're low in general, it can be fatal.
* Permanent Damage. Can't be healed without medical (could be a new skill). Resting, potions, and heal spells won't fix anything beyond that point.
* Normal Damage. Can be healed like today, and works with resting, potions, and spells.
Examples of these damages, in game and real life:
* Temporary. A fumbled blow with a sword, hitting with the flat side, causing pain. Hitting yourself with a hammer - hurts like hell, but quickly wears off
* Permanent. Critical (but not same as fatal) damage, such as a successful critical hit. Breaking a leg. You won't get better simply by resting.
* Normal. Wounds that need treatment, but general not severe, such as a normal blow by a sword. Cuts that needs treatment.
The idea is to hook up Stamina to Health:
* The stamina bar can never outgrow the (normal) health bar. This makes sense to me in the way that if you're at low health, there is no way to can have excellent stamina.
* Anything causing a temporary damage (such as becoming knocked out), should completely drain your stamina as well.
* But effects to stamina can
be countered by magic and potions. Makes them a lot more valuable.
Hospitals (please find a better word for it though, that suits a fantasy game
* If instant fast travel is available (in its current form), availability should be restricted to large settlements.
* If MW based travel (or anything more inconvenient than the current system), availability should be increased. Maybe even in wilderness.
Maybe wild animals would anolyze the situation like in real life, where they tend to attack the weakest.
Encumbrance should affect stamina (and speed and agility/dexterity) too, in a gradual way. Based on your strength.
However, for this to work it's important that we have some means of evasion and hiding too. Let enemies search in your last known location and area around it, and throw in some perception modifier on the enemy and stealth based skill for us to determine success rate. Unlike most computer based RPGs I've played where you typically attack anything you see for XP, a good GM in a dice based game makes sure to keep scaling everything to force you into certain decisions. If he lets lvl1 players face the meanest bad guys there is, that's a clue to the player - don't pick this fight, and you're awarded by having the character for a while longer. So even if the health system becomes more difficult to live with, it shouldn't automatically mean causing the game to become a reload hell nightmare.