Adding lots of pillows could really brighten up the brown couch! Love this example! Plus, getting your own fabric and making pillow covers could be cheap and fairly easy! (plus good sewing experience??)
source: Mark Williams Design Gorgeous monochromatic living room design with gray walls paint color, ivory Mitchell Gold + Bob Williams Charlotte sofa with chaise lounge, David Hicks La Fiorentina pillows, gray pillows, white garden stool, Room & Board Shinto square cherry square table, blue lamps, oatmeal linen window panels curtains, and quatrefoil patterned rug in mist.
Grounding a room with a rug is a great way to add style to your decor. This black and white striped rug adds a fun statement to this family room, and also picks up the black in the picture frames and ottoman tray, tying it all together!