The Easiest Gallery Wall: Here, a grid of six images from the same artist matches the client's clean, modern aesthetic. Note how this arrangement makes full use of the wall, meeting the lines of the top of the sofa back.
Black, gray and texture, shine. Try smoky mirrored or reflective furniture (or a mirror on the wall); a soft, low-pile rug; and a plush faux-fur throw. Shades of gray, black and white make easy partners for a brown leather sofa.