That expression is awesome! I almost wish portions of his face weren't being covered by his arm and shirt. The cloth is also super looking, great dynamic feel.
Im not a big fan of the background, not sure what would look better, but it's almost too simplistic and afterthought-ish. Also, the lightsaber looks fine to me without detail, but I would expect some kind of outlet for the right side where the light is coming out. I'm no star wars expert so I dont need the details that one may expect.
The charecter in itself is very well done..the impression on the face, the cloth, and everything else IS impressive.
But the bkground is kinda messing up the whole piece...that barcode really doesn't make much sense..and the red checker is very distracting..
I suggest that, if you can, try replacing the bkground with something simple... a brighter gradient of sorts might help...