I would do a wall unit in the center section and put the TV within that. And then I would get two matching pieces of furniture for the two side sections, some type of console or buffet type piece. I would wallpaper the three niches to give them some texture, and then hang your art work on top of that in the two outer sections

Your space is small for two different functions. You may want to invest in a drop leaf table that can be pushed against a wall when not in use. And place the mirror in the center of the wall above the table. Your green sofa does not look like it would go with your wallpaper (could just be my computer colors). If so, think about a more neutral love seat with a rug that can define the living from the dining portions of the room.

Wallpaper -- where would you end it? Just above the window? Or go all the way up to the ceiling? I think it might get confusing to see the space with the configuration of the wall/ceiling. Maybe change out the accessories if you want color -- because they are all the same in various shades. You could add interest and warmth that way using some corals or blues or another that appeals to you.

Unless I had some beloved, dear to me, pretty giant piece of art that had to be accommodated(some fiber arts are like that, for example)-I'd be inclined to leave blank