I like where you were trying to go with this, Although it looks really flat try sharpening the render and some of the effects a bit to make them pop. I like what you did with the ball in his hand but the purple color kind of throws it off a bit, the piece in general feels really washed out and dull, try adding some contrast and vibrance to it to make everything pop. I think this piece would look nice with some fractal whoring and maybe a few pentool touches here and there. Try making your backgrounds a little more interesting and work on your depth.