those tiles have a matte finish to them. they'll be fine on the floor everyone, so relax.
ortochini,,,, instead of doing a small subway, why don't you go w/a 4x12 tile? On a clients shower, I used these 4x12 white subways in a stacked pattern. I was going for more of a modern look w/that tile.
I would do white w/your blue/white tiles, a white vanity, marble top (or quartz marble) etc. Or you could do a light wood vanity. something like this:
I think if you did a navy blue vanity, white quartz top, and blue penny rounds in the niche, it would also look really nice:
For the other room w/the black white/gray tile, You could do a black vanity, (RH has a black oak vanity that is beautiful. I used it in my own bathroom. I used it in a mock-up:
For the shower you could do a black porcelain in a herringbone shown above, with the black vanity topped w/Super White Dolomite, matte black faucet, gold hardware.
Or, a light gray 3x12 ceramic tile, black penny rounds for the niche, and black vanity w/white quartz.
another darker subway tile, and a white subway tile w/gray edging, black vanity, marble top, gold faucet
a gray glass tile (discountglasstileshop) white vanity, new Caladonia granite
Walnut vanity would also look very nice.
other options
you could do the vanity in the same gray that's in your tile w/white quartz top, and a tile backsplash that matches whatever you use in the shower.
or something like this one.
this is a close up of my shower after it was done. even though my tiles are on the wall, you can see how the white subway tile looks (4x12) with a black Schluter edging around the accent design. I used carrara for my curb and black marble for the floor.
Q
Backlit mirror with blue cabinets and gray floors
Q