I think his fist is over-sharpened or something. It looks odd to me. Rather over-textured and grainy. Distracts from Sonic's face I think. The lighting is great, and I love the effects on this one. Nice work bro.
I sorta agree, maybe a slight blur should make it look nicer (though maybe add a little more to his face to increase the depth a bit more) Aside from that Great job! (the depth was already nicely done btw) B)