There is marble and then there is marble. With that wonderfully definitive statement out of the way... Source your marble, Know where it comes from. When you bottom feed on price, you can bottom feed on quality. The issue is that a bathroom shower will be demanding on a natural stone. You'll notice that some marbles look pure. They have nice white and gray tones to them, if that makes sense. You''ll see some with a yellow tone, or an occasional hint of orange. That can be in indication of iron within the marble. We all know that "rust" is iron oxide. And in a shower, a porous stone like marble, even if sealed, can wet the embedded iron and cause the stone to show orangish hues of oxidation or rust over time. Cararra, which is what you want to use, is known to have iron in it. So talk to the tile store you source it from. Some is fine, some not so fine. It's a natural material. Good marble has a tight grain. Some of the inexpensive marbles can be soft, then can pit easily, corners can break off. Some of these stones are resinated, or treated to increase their strength. The problem now is that in a shower these resinated stones can behave weirdly. They can show water differently. On a backsplash, use what you want. In a shower, you really need to be careful when you go bottom fishing on price. None of that is meant to scare you away. I's simply to make you aware. Hopefully it'll make you a smarter or savvier shopper. Since you are using marble, I highly recommend you look at using a topical membrane in your shower. That will prevent deep wetting in the shower pan and take some of the stress off of your marble. Look a Hydroban with their Laticrete flanged drain. Look at Kerdi with their flanged drain. I will gently nudge you towards either of those products. If you sway from the path, you may force me to get out my big stick. There are other topical membranes, but the key is the flanged drain. That's all for now!

The issue is the thickness of any new material We could tile the entire floor-- sire.. Then I have a lip at some point either going into the shower section or into area where the double vanity and closet doorway or into master bedroom... Our bath is not 1 room-- The vanity area is like short hall/aisle into wet area w/toilet and new shower w/new cabinetry... This house has horrible mix of flooring...white original tile in guest bath and laundry room, carpet in 3 guest bedrooms, one style/ look of mid-brown LVT in guest hall and front 2 living/dining and den, 12x12 gray LVT in kitchen/entry, and a weathered/limed oak in master suite area... So 5 different flooring looks...I hate it...but re flooring in 1 uniform flooring is way more expensive that we see a need to do from practical standpoint... I am trying to avoid having a 6th flooring look by doing something separate in one or two areas of master bath.

For the window, you could try a cream linen with trim the same color as the walls. Beautiful wall color by the way. I agree that cream or ivory would work for sure for towels. But you could try chocolate brown just for the drama. I'd probably buy something returnable and bring it home and see how you like it. With the cool sage green on the walls though, it might be too much brown. If you could find a malt brown or greyed brown (which I can almost see in your floor I think), something between cream and chocolate, it could work as a nice compromise.

The gray trend is over. Forget gray. Work within the tones and shades of the wood floor.