Thank u in advance for suggestions!!

If you like turquoise, it would look nice as an accent wall. You could then add turquoise pillows on your couch. Or you could paint it the same grey that is in your carpet. If I could also suggest that your large round mirror may look really good above the couch. Then move the rectangle poster (it's too near the ceiling) to where the mirror was approximately and slide the small black framed picture over and wall could still feel balanced.[houzz=]

agree -- either that one wall some accent color, or all of them a neutral-ish color that pushes off more from the couch (either much lighter or a bit darker in a clearly different shade -- green?)...

If you can pull it out a little from the wall and add a small sofa table behind it with some decorative objects to break up the color then I think that would look really nice.

Adding art on the wall behind the couch, and using pillows and throws will make a difference, too. Maybe enough to leave the walls as is.