- the quick and dirty critical injuries system;
- the rewrite, which eliminated the wound point values and aimed shot penalties.
I need to make clear my intent: I want to add detail without adding the kind of fiddly numbers that Roger referred to as "Runequest mentality". For those who don't know, Runequest had hit points for each location and (I believe) penalties to aim for specific locations. I'm unfamiliar with Runequest specifically (played CoC and Stormbringer, but I don't recall either using the hit location rules.) However, I played a lot of GURPS and The Fantasy Trip, both of which had alternative hit location systems: you could either roll 3d6 for random location of injuries or take a to-hit penalty based on the approximate size of the location to directly injure that body part. Hit points for each location is a fraction of total HP, plus injury to some locations could invoke special rules.
I want just the last bit, on an ad-hoc basis, using a universal technique: aiming at a specific body part and successfully hitting tags it as "injured" (increasing to "badly injured" or "permanent injury" with each successive strike;) also, make a Con save to avoid immediate loss of the body part. This system doesn't replace hit points, but is a risky option that might end combat sooner. The average opponent will save 50% of the time, so it might make more sense to use ordinary melee for low-hit dice mercenaries, goblins, and the like.
So, we get to the question limpey raised: won't this mean that PCs will always aim for the exposed parts of the face, making combat pretty repetitive? Maybe not. As I said, it's a risk; even if you hit, you might not gouge out that guy's eye, or break his jaw. Some weapons, like axes, might not be usable that way. If your opponent has a longer weapon, he might simply move out of your reach. You might prefer to wear him down the normal way, especially since even an opponent with one blinded eye can still potentially attack Do you really want to poke everyone's eyes out, one by one, while they hack at you?
If so, fine. People do try to aim at vulnerable spots in a fight. Which is why armor was invented.
There is another matter, though: if you do strike at an opponent's eye, he can still sacrifice his shield, if he has one. He can sacrifice his weapon, with a block. I'd even treat helms the same way: if an opponent scores a good aimed hit at the head, eye, or face, he can opt to turn his head and let his helmet catch the blow and be knocked off or damaged.
This feels about right for me, because it adds more details to fights and more character to veteran warriors without very many mechanics.