Thought of a couple new things, which may just be updates you made since I posted last.
1: It doesn't say how many XP you need to gain a level. 100?
2: You don't explicitly say how items are identified. If someone finds an iron dagger, does he know it's not a steel dagger? What about a bleeding potion? I suggest making up side effects of potions for yourself, so if someone tests one they can try to identify it.
3: It doesn't say about non-combat skill use, but it seems like you still roll 11+ on d20 to succeed, modified by skill bonus? That is, high-skill people tend to bandage in one turn while unskilled people can take multiple turns per bandaging.
4: Again it isn't explicit, but it looks like when you learn a skill you gain it at +0 (removing your -1 unskilled penalty) and then subsequent skill gains in it give you bonuses.
5: Might want to put the armor defense die roll in parentheses for people who can't untangle 5-10 (d6+4 I suppose).
6: The power roll, while novel, doesn't seem needed since the damage roll exists to show how tough the hit was. The attack roll can be used for a fumble / critical resolution (such as your 1- / 19+). Removing one die roll per combatant might not seem like much but it really helps in large fights.
7: I suggest a potion that you pour on armor to strengthen it, similarly you could pour on weapons, and it effectively upgrades the item to the next higher level. Poured on a person's skin it grants a 10 HP buffer which is taken as damage before your own HP and can't be healed (so it's a temporary effect). Quaffed the potion acts as a powerful laxative.