I'm in the same boat as you! I currently have a tapestry hanging above my fireplace, but I'm getting ready to paint and soften the colors of my room, and am looking for fresh ideas. Here's one I found that I really like. Maybe it will help you too!
The link to the post is broken, but here's the link to the blog in case you want to check out more ideas: https://www.worthingcourtblog.com/
You could shorten the look, ( sending photo) then above as in photo, one very large painting, or two. Or a mural directly on the wall. Or a large wall sculpture.
You could make your own art work on three vertical boards, with the middle one being a little longer. There are some great DIY art ideas here https://www.hometalk.com/search/posts?filter=Diy art
I did mine in oblong 26" x 6" travertine tiles in a herringbone pattern with gray grout
darn, go to Houzz.com and search photos for herringbone tile fireplaces and you can see the affect.