I prefer limb loss can only happen if reaching zero hit points. That is the only time that lethal hit can happen. With a wound system, it is "life or limb". When reaching zero, there is a chance of a hit to the limb. There is a simple d8 check and a similar but more accurate d20 check.I can only speak for myself, but the notion of instantly healing major wounds by telling someone to buck up just doesn't pass the sniff test. Now, I don't treat all hit point damage as actual deep cuts or major impact wounds, but I do have a 'colorful critical hit' system that flavors crits that do enough damage vs. your current hit point total as, well, deep cuts, major impacts, etc. That's typically how you lose body parts in my game- which is not common, but is common enough to make the regenerate spell valuable even in editions where it doesn't heal hps.
I get what you're saying, but for me, "does this make sense?" is more important than "does this math work?". That's why my tentative set up for Get Up! doesn't actually heal- it's designed so that you can keep going (and the warlord can also use inspiring word on you on the same turn) even though you're beat to hell. I really don't want a martial healing option that has no explanation. Even the Healer feat requires you to use bandages and sutures and whatnot (in the form of a healer's kit charge)- it's on the edge of what I consider to be believable.
And don't get me wrong; none of this is meant to disparage "real" martial healing for those who like it. It's just not suited to my taste.
d8
1 head
2 chest
3-4 abdomen
5 right arm
6 leg arm
7 right leg
8 left leg
If the injury is to the head, chest, or abdomen, then the character is unconscious, and death saves are normal.
But if the injury is to one of the four limbs, the character remains conscious, and death saves can result in loss of limb.
Fail death save once, limb incapacitated 2d6 days.
Fail death save twice, incapacitated 2d6 weeks.
Fail death save thrice, incapacitated 2d6 months, roll again.
Fail a fourth time, permanent loss.
Only healing spells of level 5 or higher can heal or regenerate a limb.