Your characters' legs are bent, so I'll assume he's not standing straight either. Most pokemon sprites, standing straight or not, have shading on their legs beneath their knees, unless for good reason.
(
) See?
Also, since this is, after all, a pokemon
battle sprite, I'd think you'd want a fairly actionate sprite. You know, cause battles are actionate. And standing straight (which your character isn't doing, by the way) isn't actionate. See all those sprites in the pokemon thing? Yeah, they mostly have a fairly dynamic pose, or at least a characterized one. Your guy's kinda just standing there and, like...chillin' wit' his ball out...His pokeball, that is.
Also, the hat would be casting a shadow on the face, and the head would be casting a shadow on the body.
The idle arm is too short and skinny, and the other a bit long.
The neck should be attached to the head further back. Now it looks like the head is attached by the chin.
Honestly, I think the legs are cool, (Just shade them, and do the colored outline thing like you did with the shirt) and the face is alright (just shade it) but everything between is just too plain and boring and...paper-cut-outy to be interesting.