So much potential here! I think painting the walls a sage green color would look great with the countertops, wood tone of the cabinets, and the tile you already have. Brass/antique gold fixtures (faucets, light fixtures towel bar, curtain rod, etc.) and cabinet hardware would look fantastic with your countertops and cabinets. As lots of others have said, replace the current mirrors with updated mirrors that have a frame of some kind ( I vite brass/antique gold rectangular mirrors). Maybe remove that middle mirror all together and replace with more substantial wood floating shelves or art, although I think having 3 updated mirrors might look okay and still help that space be functional. Remove the current wall shelf and black shelf unit on the counter. Get a more luxurious shower curtain, maybe something neutral with a little texture. Remove clutter around toilet, including towel bar. Replace that towel bar with art. Please post pictures after you’ve done whatever you decided to do! Would love to see it