First of all, you are not required to have an accent wall. There are some folks who believe it's on it's way out, anyway. Second, I would recommend swapping the positions of the sofa and loveseat, to have a smaller, unfriendly, barrier for your arriving guests. Normally, wall color is best chosen from a rug or well loved piece of art. Since you don't seem to have anything that isn't neutral, you can do almost whatever you want with wall color. Bring home several sample chips, place them on the wall and live with them for a while, through all the light changes during the day and night. Another option would be to add some color and life with some multi colored drapes through the entire space, using one of those colors for the walls. The ledge over the tv wall could hold a few trailing plants or a few large jugs or vases or plates, or whatever. A chair on the wall to our left of the TV might be worth considering. Good luck.