Hi, fellow home artist! I have a music room, the ceiling of which I painted as the winter night sky in glow-in-the dark paint for the stars. So, the ceiling is really imitating the winter night sky.
I think you have to be the one that originates the mural fully. What feeling do you want your rooms to have? For me, I'd go with a relaxing bedroom, a strong office, and a lively kitchen.