Try watching a game called Beyond the Beyond. In Beyond the Beyond, characters have a first HP bar, which works pretty much as energy shields in spaceship games. When this first HP bar depletes, the character gets stunned and doesn't acts until some turns later. Then is the second HP bar, which is the actual character's life. If this goes down to zero, the character dies.
There was someone's RM game where it used something pretty similar. Characters didn't died permanently, they got up with some HP after a while. But if all characters were dead at the same time... well, you know the consequences.
So, using this kind of stuff (or others, who knows) can make it completely unnecessary to revive characters,
Orochii Zouveleki
EDIT: Another idea. Characters aren't dead at zero HP. They're dead at, let's say, -700HP (let's say the character has 1400 maxHP). When its life depletes to zero or less, the character gets incapacitated. But you can "revive" it just using a regular recovery spell/item until its HP gets again above zero.
A little of this can be seen at Mabinogi, where exists a chance of not dying if your HP is like -400HP and your character had a maxHP of 200. It's called DEADLY status. Still, while on deadly, ANYTHING (even a small breeze) can kill you (except for healing of course, you can heal back to normal, that's the idea of it existing, because there are some insane monsters that deal like 10000dmg and the max HP I think one can have is like ~800).