hmm not bad, its a bit flat, I think his back arm is a little too faded other wise it looks pretty good
try this, not sure if it will work because I would have to experiment with it, but un-fade the back hand, instead put a light blur on it, and put a dark color balance/gradient layer over the whole thing. after that try using the burn tool lightly over the top his back arm. try that and see how it looks.
it looks better, but it still seems the render stick out too much from the background(on-top of his arm is where I really notice this) I'm not sure exactly what you should do, experiment with some different things, try to improve the flow
Okay. I took some of your suggestions and changed it around, added some detail and created some flow.
V1, you should mind the lightning, it's not coming as big from the back as you made it, it's mostly coming from the front, v1 has the best colors, it's got good contrast. You should work on your depth, cause it looks a bit flat now, and last but not least, on both the left as the right side you have somee white effect, i would remove that if i were you NJ!