I’m confused as to whether you’re planning other major thing just to mitigate the fireplace.
But overall if fireplace is staying, I agree with leave it very simple, no camouflage, no art above. Let it become” neutral”.
Then examine room for where to put other art you love, furnishings and colors that work and are updated ( not “ modern” per se but good lines, good quality) so that these things are the stars of the room.Also re- think any layout changes that help, direction of seating, TV placement & styling, to optimize the “ flow” and comfort in the room.
Q