I wouldn't necessarily hang anything else on that wall, but rather try to balance out the empty space with other items that sit on the floor and add height to the TV wall area.

Seems an odd choice to have the round end table and lamp in the window. What if you moved it to the end of the sofa, nearest to the tv, wall. It might help to visually balance out the TV. The place a floor plant in the corner where the window wall meets the TV wall.