Agree with everything mike has just said also his hands are looking a little small (and missing a finger?!) and there seems to be no real center to the fire ball so its kinda like a floating fire cloud...

Finally the shot imo doesnt work. it all looks a little lost as there is so much empty space. Have a look at some portraits and see how they look to get some ideas.

On a plus note the modeling and texturing looks great but will need to be tweaked for the final image/pose (i would suggest doing this with any still image as things can always be touched up )

T