This is a tough one. I'd probably do a small sectional sofa, positioning the back of the sofa facing the doorway with its right sectional arm facing the long wall. Then put the t.v. in one of those cabinets with a video lift in it with its back facing the hallway. Or you could flip it--putting the back of the sofa toward the hallway--maybe put a narrow sofa-table behind it. Another alternative is to have two small sofas facing each other in front of the fireplace and the t.v. along the long wall in a video lift cabinet, which would keep it from competing with the fireplace when not in use. If a cabinet is out of the question--expense-wise, you could mount the t.v. on the long wall and then hang a curtain rod above it, creating a false window. When the t.v. is in use, just open the curtains. Or not....  ;)