Theres no snap! Go look at some street fighter sprites, and you'll see that in one frame, the leg is coiled ready to strike, then in the next it is all the way extended. This gives it a good snap, and makes it look like it would actually do some damage.

no, i think he not. maybe some single pixels can be moved, but all the head haven't to change it's position.

he probably should change his head tilt.

yes we should :P when he slides back, he has idle animation from my previous piece in my gallery. Check it out. Gloves are little problem, but I think it isn't very important detail in in-game action, when two characters are in a dynamic fight.

when it slides back shoulders are weird. the gloves seen inconsistent when he is still and moving. when he is still shouldn't we see fingers on right hand?

Yes, I did it several times... Now I see: in the end of kick, before return he should has toe turned to spectator. He "wanna" kick with all the surface of sole... I did it one time again in real.... right hand shouldn't be behind him, it should be in front of the waist....

I'll make 3rd version... :P

Have you tried doing this kick in real life, just as you have animated it? I think you'll find that it's a bit cumbersome, especially the part where he has his feet together before he kicks. And there's something about the foot that disturbs me, a kick with this kind of force would probably try to hit with the heel, rather than the tip of the toe. So you might want to put some more emphasis into that, you might even want to remove the "toeflip" he does at the end.

 It's nice, but for some reason, when he put his feet together there is a little pause that bothers me, because it breaks the movement. Also, i'd like it faster, especially in the first frames.

Anyway, nice work.