I agree with Brandi - a long console table or sideboard with lamps at either end would look lovely. Also the piano area would look great with a bigger picture above it to balance things out.
Looking at the art initially I thought it was an internal obscured glazed window. I think if it had a feature picture frame that would help. Also a more intense wall colour would help it settle into place. I agree something under it would make sense - if you can fit it in the room. Covering the vent whilst still allowing it to do its job would be great. Good luck!
Brandi Nash Hicks
Hayley Perry
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