Nice room. If it were my client, I'd do a pretty spectacular art wall. Think "Downton Abbey". A mix of oil paintings, charcoals, watercolors. Varying the sizes and the types of frames is key. I'd fill it from around a foot below the mantle top and go pretty much up to the ceiling. Mix of traditional and modern--i.e. a Picasso print next to a simple old oil portrait. Art wall would help make the TV disappear as well. Thank your builder for centering the fireplace correctly...I could tell you some horror stories :)

I finally finished the wall. Took some thinking, but turned out perfect.

Wow, very nice, that's a dramatic difference! Also, your dog is very cute and seems to have the best seat in the house :)