In my current campaign I've been playign with any time a character would be knocked below 0 hp they have to make a save vs death modified by their current HP score.
Make the roll and one's demise is beign preemptively considered, they actually have 0 hp and are simply unconscious.
Miss the roll by 1 to 5 points and lose a randomly determined ability point.
Miss the roll by 6 to 10 points and lose 1d4 ability points from a randomly determined ability point.
Miss by 11 or more points and the character is dead
So far 1 point of STR had been lost, as has one point of Wisdom and 4 points of CON, all among 3 different characters.
The permanent wounds are records on the off chance one discovers magics or artifacts able to cure such mangling.
Getting the stuffing knocked out of a PC is serious business even when bandaging allows a generous hp restoration and death isn't always certain.