I think you should crop your balls a little bit. If you clip off a little of your balls it won't hurt too much and it might make for a more interesting composition.
very interesting choice of subject - I have several of these things lying around somewhere, and I've always thought that they look cool. your lighting is way harsh, though... have you ever tried constructing a soft box? this can be as easy as propping up a large plastic bag with a couple of pieces of cardboard. then just stick your subject inside this bag and point a light through the bag. you'll get a much softer light that way that renders good shadows and detail.