I think if you select a wall color that is too well coordinated to the tile, it will only bring out the vibrant pattern in the tile. So pick colors you like. Let your personal style and the vibe of the rooms dictate the colors. Your walls, furnishings and accessories will take center stage so you won't really notice the tile. Area rugs will down play the tile too. Ceilings are a great opportunity to add color also.

Sorry,your picture did not make it onto your post...try again?

Maybe these will help you in making lemonade out of the lemon (which I don't think it is)Where else are you putting the beige tiles? And where are you putting the mosaic.Perhaps ramping up the black in accents will legitimize the beige and blackhttps://www.houzz.com/photos/jane-lockhart-interior-design-kylemore-model-home-dublin-traditional-bathroom-toronto-phvw-vp~1267669

I use a ph neutral tile and grout cleaner Home Depot sells in their tiling section.