Light colors on the ceiling lift it up to feel like a larger space. I would stay with warm tones, rather than cold ones. If it's a nursery, it might also be nice to paint trimwork white for a little pop. We live in Seattle and changed our living room from a cold light blue to a warm cream tone. It was amazing how much brighter it seemed. As far as faux techniques, I don't have any suggestions, but a mural might make the space feel larger as your eye gets lost in the scene. Good luck.

Minty green,bright yellows (doesnt have to be canary),baby blues,and bright whites.