• TV has to be over FP as there is no where else in the room
• You can't do built ins any deeper than the wall space at the windows
• Likely you'll want to do drapery panels at the windows, so the built ins are not really an option

The stone on the 3 sides of the FP should work, but consider placing cabinets or chests on either side of the FP with art/mirror above.

I think a simple fireplace surround and hearth in stone and a wood mantel are timeless. You can order the surround from mantelsdirect.com.

http://www.mantelsdirect.com/facing.html

I like the idea of chests or cabinets with mirrors on either side and then you will be able to have draperies. The stone you selected won't add much to the fireplace. The only concern I have is that the TV might be mounted too high for comfort, so keep that in mind when you design the mantel.

Mantelmount.com! We love ours.