I think your best options are to either carry the shower walls onto the floor, carry the shower floor through the space, or, pick one color and size from the shower to put on the floor.

Thank you! Yes, extending the existing tile would certainly be a safe bet. BUT we were hoping to brighten up the space with a lighter color on the floor. Do you think either of these would work?

Maybe if you used the lightest color from the shower.

Gorgeous! I love your bathroom materials. May I ask why you are abandoning the wood flooring? I can guess but don't want to assume. 

I vote to choose a solid floor slate of the color of the darkest tile in the wall or slightly darker. My daughter has a dark grey colored slate look floor in her master bathroom and loves it. I've heard others complain dark surfaces show light specks but she says it's not an issue.

If you want the lighter color, make sure to match the new color with the most prominent hexagonal tile in the shower. and check for coherence with the countertop and cabinets. You may have a problem with different whites. Do you have any dark tile samples you can take a picture of?

Are you replacing the wood because it is in bad shape, or because you are tired of it?

Your barroom is beautiful. I would do navy blue floor tile, almost black.

I think a pattern would be great if it is the right pattern. If not, it could be all wrong.

ETA. Nevermind. I see you want a light tile on the floor for brightness...