Not a bad coloring job! For the stars I would reccomend switching the colors up here and there very slightly, if you want to make it look really nice put in a glow-dodge layer behind them, turn down the opacity and then add similar colors behind the stars via airbrush to make the sky look really lit up! If your adding character shading too, its very nice to let the glow-effect bleed slightly onto the character too if you want a more abstract look to the highlights.

With an ass that big, you could probably live on it. X3

So big you can't tell what's what on him. Wow.