Separate your wall colors. This is SUCH a good idea!! I dont like two colors coming together on a corner and this is the fix for that! This would also be a great fix for the beat-up corners in the house.
For Master Bath - To add a little interest to the plain walls, add some 1" by 4" boards to one wall. Adds a little architecture to the room...a coastal cottage feel, no? :) Just glue and nail gun the boards on the wall (easy), then paint everything (possibly a cool white, like Dunn Edwards, Swiss Coffee) to expand, lighten, and freshen-up a small, windowless space.