Although the shelves are great, I think they have a rather cold, sterile feeling. Painting the backs might warm it up a bit, but what might work even better is creating your own fabric inserts. You can follow the instructions on this site: http://theblissfulbee.com/diy-fabric-inserts-for-shelving/. I made one for my television armoir in my bedroom by cutting cardboard to fit and covering it with textured floral fabric. It's a temporary way to get a big impact that you won't be stuck with if you change your mind in 90 days. Even if you don't use a printed fabric, adding something with texture, like a beige burlap, would bring some warmth to the room.