maybe make him a little less symmetrical or angled. At the moment he's standing up like a soldier, he's in kids form. you can make him put his thumb in his mouth or something when he's not moving.
Matt's version has a slightly different perspective methinks (I'm no expert, but that's what it looks like)
put a dot at the very middle of Matt's BG and try to figure out the perspectives by drawing lines, connecting to the various objects, then apply as close as you can that perspective on Jame's sprite.