Realy nice~ the colors, the background and the drawing style is very nice and relaxing.
Excellent. Reminds me of the SMW night snow levels.
I wouldn't worry about the lighting, it seems to me that those bright, wonderful little stars do more than enough to light the scene. Plus I think without the contrast it would not be well off. In my opinion of any game environment, if the land/platforms are dark, the sky/background should be bright, and vice/versa.
What I meant by my unnecessarily long comment is I like it just how it is