Put a gallery wall in an unexpected place. Like over the tub in a bathroom in this photo from The Fashion Medley. In your laundry room. In your master closet. Why should the joy of a gallery wall only be for those who enter your common rooms?
I like how the tile finishes and comes around to join the painted wall and the black tile detail edging. Preppy traditional bathroom with grey walls, white subway tile and black and white shower curtain.