I really like this idea, when changing your skin in your Profile you can choose Male or Female hurt sounds, or the default we have now. By default if you don't choose anything it would be the sounds we have now.
I love all of these. However, owls should still be heard in cold biomes (Snowy Owls), but not in oceans or lakes obviously. Also, I think the Witch's noise should be a more female, menacing version of the default villager sounds.
I love these! However, the Endermen should come out of a black portal that suddenly opens up and vanishes (Like the End Portal, but Endermen sized and vertical). Also, chickens should be able to eat grass to regain health as well. I agree zombies should have a clawing animation, but pigmen, sword wielding zombies and wither skeletons should swing their swords like a zombie or like a player. Also, skeletons should draw back their bow like a player, so you can see when they're about to shoot, as well as Skeletons clawing out of the ground like zombies. Pigmen should also come out like zombies, and creepers should have an animation where they look like small green creeper-like mushrooms, which then begin to flash white and grow into a creeper.