I'd suggest losing the dithering in the window. For such a smooth surface, dithering may create the illusion of rough texture. Unless it's supposed to be a dusty, or muggy window. Still though, I'd lose it.
In fact, I don't recall iSTVAN ever using much of the dithering technique. I believe his style was more flat, and simple. I would also try fattening up the black hole character, as he's not usually the fittest of super heroes. Not huge, just a wee bit chunky...and bulge, definitely need the bulge...Great interpretation any how...