Have you considered wallpaper? This is especially good angle if your bathroom is smaller and you want to decorate it without excessive amount of things. Simply putting wallpaper on the walls will do wonders.
You can play with color, geometry, style.. The choices are endless.
Start by choosing the wallpaper then decorate with hanging art, mirror and matching other details like shower curtain.
You might make your bathroom a place where you’d want to spend more time in.