Love the concept, but I really would love a bit more light on his face, and angled so I can see a bit more of his expression. He doesn't need to be looking at the camera, but just so we can see the intensity I think is going on in his face.
One bit I'm not sure about is the black shirt on the black background. I agree, try and keep it a low-key image, but I can't help but thinking that there's got to be a better shirt he can wear, or maybe make the background a dark shade of gray. I'd just like him to stand out from the background just a tiny bit.