Would not hang tv over fireplace....remove right window...make a built-in for tv so it is at proper viewing level....that way you can cover up the big firewood holder on the right....something like this but switched to rightside...

Please read concerning the placement of your TV:)

https://www.houzz.com/discussions/on-my-soapbox-mounting-the-flatscreen-too-high-dsvw-vd~4537748

demo the wood box side of the fireplace. build in television unit on that side. Change side windows to smaller ones to accommodate built-ins.

I think your fireplace looks very nice asymmetrical. If you decide you could leave it as a natural wood burning fireplace then you can fill the opening on the right side with wood as intended. Above mantel, do not centre your tv above mantel...instead centre your tv on left side in relation to firebox opening. On the ride side of your mantel above the wood holder box, lean a beautiful painting and two weighty looking candle sticks. No demoing and your windows would not need to be changed. As another poster said, you can add symmetry in furniture arrangement and then the asymmetrical firebox would become a design feature.

A quick sketch...

vaulted our living room ceiling with this distressed wood.... looking into the idea of beams any suggestions?