heh, it looks good for a sprite a bit above half that size :p
remember, detail to size. This sprite looks like one of those cheap "hi-res" sprites abundant in editing boards, because all the lines are scribly and there's lack of detail.
if I was you I'd resize this to something a bit above half the size, because the configuration of the shade is clean and looks good, but all the actual details are very sloppily made, and all of the actual shapes are very unprecise. You should also work on the pallete, the skintones need more contrast.
after that if you want take a new stab at a fighter sprite, but remember you will have to put much more detail than this, and really work on your lines.