I think large white subway tile would look better in the shower. Those two patterns don't really go together to me but I'm not a designer.

Not sure about the grey cabinets with the grey floor either.

I agree on the shower tile. I think it’s very busy. But I love the big size organic looking tile.
The gray cabinets are fine.
I’d probably do a light wood tho if possible.
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What do you not like about these choices? What does and what doesn’t work for you? What’s your inspiration like?

Make sure your shower floor tile is not too slick, charcoal penny tiles or pebbles would go with your other choices. Remember that counter sample is small and the bold veining might be too busy on the counter. There isn't a lot of contrast between floor tile and cabinets and it looks a bit like concrete. I might get a darker tile or in a smaller bath use a lighter floor-rated tile in both the shower and on the floor. Or keep the larger grey tiles and use a shade darker on the cabinets. Just a deeper grey would work but a deep grey blue or navy with those tiles would be awesome.

I think it is not quite right.

I would use the term “designer” loosely. Trust your instincts. Bathroom dimensions? Unless it’s the size of a small aircraft hanger that floor is a no. The shower tile and countertop shouldn’t be within 30 feet of each other. I’m sorry this happened to you. There are so many lovely choices, but this really missed the mark.

You might want to reconsider doing the grey flooring with grey cabs and we agree that you might want to do a white subway tile in the shower. Here are a few designs from designers I follow that might help:

Boca Raton · More Info

Hampton Boathouses · More Info

Sun-Drenched Elegance · More Info

Hip Master Bathroom · More Info

Hip Master Bathroom · More Info

What doesn’t jive for me is the ‘concrete’ look floor (which I like..) with that cabinet front style. Then two marble looks on top of that makes for too many directions for my personal taste. I don’t think adding subway tile instead of the shower tile will help (plus, more grout to clean). Nothing is bad looking on its own, it’s the mix of them that I don’t love. I hope all works out whether you move forward with these selections or not. It’s your bath, so whatever you like is what counts!

I think the two faux marble samples clash -- one is visibly more yellow so you should select one or the other and choose a simple white that coordinates with the one you select.