This is what we used in our mudroom, hallway and powder room (which is off the same hallway but not visible in the picture.) We like it and we get alot of compliments on it. It's 3x16 set in a herringbone pattern (Crossville Tuscan Clay series in Maronne.) It's smooth and easy to clean, and the color variation hides dirt (we have a puppy and 2 kids.) It's next to the hardwood floors in our kitchen, but down 2 steps so there is a natural transition. Here's a view that kind of shows it by the wood floors. HTH

Weedy I know you constantly renovate properties and the idea of redoing a bathroom now, and then having to redo it again in 20 years doesn't seem like a big deal but I don't think it's very sound advice to say not to worry about it now because you are going to want to do it over later anyway. (And that's probably not really what you mean anyway) There's a big difference between updating a bathroom cosmetically and having to redo it for functional or accessibility purposes. There's nothing wrong with getting an accessible door (32'-36" wide), an accessible shower (Even if not technically fully handicap accessible) and a layout that it at least fully adaptable NOW, and not having to think about it again. It would be very easy to get the shower right and use a wall hung toilet, and with the vanity and linen cabinet toward the lower right corner at least get the Plumbing right for a wall hung or accessible sink with finished floor and wall around it. Then you could install a more conventional vanity and a linen cabinet for now and if you Need it to be accessible in the future take out the conventional cabinetry and put in the wall hung sink

Spend the money on a good waterproofing job in the shower and bring the sheet membrane or Hydroban etc a foot or two outside the enclosure. Then tile up to the ceiling in the shower...or at least a fair way above the shower head. There's no need to tile the walls outside the shower. I didn't tile outside my shower enclosure and I have no problems. I dry off in the shower and step out and the walls outside the enclosure are perfectly dry. Tile outside the shower is mostly cosmetic, unless you are doing a complete wet room.

@Angela - The OP's first paragraph stated marble over a concrete slab. " I really think you should remove the old tile." Why? If it's set properly It should last the lifetime of the structure. Bonding to it is not a issue. You'd need to remove the underlayment/top layer of subfloor to even the floor anyway after you rip out tile. If this was wood framed how could you determine that without knowing what underlayment was used and condition after rip out? Plywood, mud bed, CBU's, uncoupler, antifracture membrane etc. The OP is trying to gain height. Most likely you can leave the underlayment in and apply a self leveling underlayment on the top to achieve desired height.