i think its great for ur first sprite, im not a --- at these my only suggestion would be to have some more belnding on the sprite somwhere ^^
Left side looks alittle to plain, try to spice that up some. Also try some overlaying effects on the sprite.
You can add some effect C4D's going from his feet to the top left and top right. That would make superb effects to this tag. If there is a colored version, I would like to see it.
I think some arching effects from his feet to the top corners would be KICKIN. Try that. And can I see the colored version?