I like (and wonder) how you did the tiny spots of light in the city. They give a very eerie look to the image -- almost as if all the stars of the sky were instead clustered there.
Beyond that, I don't really fall for the large buildings. They seem too strangely placed, and out of proportion (not only between the city, but in respect to themselves). The sky is very nice, with those blurrings around the stars. The moon could use some crater detail, perhaps. And the planet definitely could use some more work. The sea shades give a very still and quiet feeling to the image. The ambient light of the city does a good job lightening the sky behind it.
The small lights are several random hand-drawn lines (scribbles ) with the line type set to dotted (each with different spacing). The stroke colour of each line (there's about 4 or 5 maybe) varies as well for a more random effect.
You're right about the buildings, but that's kind of the effect I was going for. At any rate this is basically just a digital sketch... if I ever make a more detailed version I'll keep your suggestions in mind.