Here's my advice... When I decide what I'll be hanging on the wall, I'm connecting it visually with what is below it. So what you have below your empty wall space needs to look like it's something.
Right now the chair looks to be just set there, not really part of the space, and it appears you have some black boxes or something on each side of the tv. (or is that an ottoman on the left? sorry, kind of dark, I can't tell)
Can you instead make the furniture arrangement look like a plan, and then do a asymmetrical display on the wall. I mean not the same on each side of the tv. When you do it the same on both sides, it only brings a ta-da attention to what is in the center of the symmetry, in this case the tv, which isn't something beautiful that we'd want the focal point going to.

So, can you bring the chair over to the left of the tv, out away from the wall a bit, and angle it in towards the center of the room, have a small side table and lamp with it, creating an inviting area, and then find a fun painting or print you like that is taller than wider and hang it just a few inches above the table area... (like 9-12") That way it will connect with the seating area, not the tv.

I'd also consider moving the tv to the right just a bit, (like 18") and playing up the new seating area on it's left more. Then get a couple more tall vases, even larger than the one you have shoved in the corner... all different... and set the group of three to the right of the tv. Add some interesting twigs, curly willow etc. to them. That will be a nice interesting texture to look at from the hallside, instead of the side and back of the tv.

Hope this all helps!
Liz www.HometoCottage.com