I’d probably look into a cement FP finish. I think that would look great. I’d do it where the tile is and the middle bump out above the FP.
If that doesn’t speak to you, you can go to any tile store and find something you like. Do that for the FP. And maybe wallpaper the walls above the FP.

Or you can do a tile with shiplap on top for more of a beach feel.
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I like the shelves on bottom. I’d fill one up with some wood. And one with something. Decorative. Maybe a stack of books and a small, short vase of pretty flowers. Or a candle.

.....

There’s so much you can do, enjoy the unlimited options. And have fun with it.

I have such a hard time with unlimited options! I’ll google cement FP finishes. I appreciate your suggestions 💞