For starters, I would take down the pic over the tv, the clock (?) and the blue picture. Center the tv stand on the wall. We really need to see pics of the entire space, from different angles to make additional suggestions.

I would either centre the tv on the wall or slant it fully in the corner by the fireplace. If the tv is centred on tv you could centre the picture above it, otherwise remove it. Take your blue picture by the fireplace and hang it with your other blue picture in your dining room. Move your two closer together.

I wonder if the tv is not centered because you need clearance to enter and sit on the sectional there? I'm thinking that your furniture is quite large for the space. Would it be possible to remove one piece of the sectional? Then I would agree to center the TV and stand on that wall.

The blue pictures together look so much better 💙