its missing the wow factor like some may call it... I mean the lighting is correct, the signature is not bad but its missing something that will make it FANTASTIC that "it"
First of all, I liked what you did here on your tag.
2nd, I hope you get a better render because i really can't see the right part that well but darkening the right part while making the left part a bit lighter is a +1 for me.
3rd, I think Cap't America was saying "EGGS!!!" in that render...