Have you thought about buying a new couch? Sounds like your room is really too narrow for the type of sectional you have. I'd think about going with a couple love seats and a couple comfy chairs instead of a large sectional. Then you'd also have more ways to set up the room.
In our old house, we had a very long living room. The fireplace was on the long wall with a wall facing it, where the couch went to face the fire. We placed our entertainment center at the corner of the room between the fireplace and the sliding doors to the deck at an angle. We placed a love seat at the other side of the fireplace facing the tv/sliders, leaving 1/3 of the room open for other furnishings....a bookcase, sofa table, large plants.