I beg to differ on the effects of blue it might calm but it also depresses and acording to feng shi is not a color for any place you will sleep because of its depression effects
nuturals are best because warm colors invigerate you making it hard to sleep and cool colors will make the room feel colder and less welcoming
not to say you can't use a warm shade if its mixed with nutural (i.e. a cream red color would really be more nutural then warm)
that comes from having a painter for a dad and having studied feng shi and the effects of colors