Take a look at Simple White thassos-lookalike at Tilebar. Get a sample, though, pictures don't do it justice. We have it and love it. Everyone who sees the bathroom thinks it is marble. We did our master bath in gray and white. The white was the Simple White, the grey flooring is Timeworn by Artistic Tile. It is a very neutral low pattern that is porcelain but looks like stone. Then our deco mosaic is a pretty grey & white that ties it all together.

https://www.tilebar.com/collection/tile-mosaic-collections/simple-glass-thassos.html

https://www.artistictile.com/timeworn-light-grey-ptwgrylm24

We deliberately chose low pattern things so that we could change other decor items easily. Hope that helps!

Thanks, I checked them out. They do have some nice tile selections

Have you looked at the newer mirrors with internet access? I'd try lowering the lighting fixtures, or looking at longer ones, so as to reduce potential for shadows. Jean's suggestion is a good one. Hard water and marble do not play well, together. Will you replace the triangulated seat for a bench style? Are you considering adding a more contemporary style grab bar anywhere? Would you consider a tile with dark veining for the lower tile in the shower? How large a tub are you seeking?

look at Bedrosians. they have their own, and also carry other companies on their site. there are hundreds to look at (was just pursuing yesterday and saw many of the marble look tiles)

otherwise, go into a nice, large tile store and check out some of the samples on display. if you want fine quality, you will have to pay for it. Italian porcelain. as mentioned, Tilebar does carry some nice faux marble

https://www.tilebar.com/collection/porcelain-tile/shop-by-look-porcelain/marble-look-porcelain-tile.html

this one is pretty real looking

https://www.tilebar.com/marble-tech-bianco-gioia-24x24-polished-porcelain-tile.html

I'd take a look at new layouts and tile floor selections

love the ones w/the built in shelf around the tub

i know you said freestanding, but something like this is so much nicer. and easier to clean

Have you seen AnnSacks tile website? Great choices/designs.

Daltile's Marble Attache Lavish is a great choice as well. Looks like the real stuff.