I know but I'm playing the role of the project manager and trying to coordinate between different people - thank you for sharing your thoughts!

I'm not sure what your question is regarding recreation as I am in the middle of my current remodel. I just selected the dining chairs this week and test "drove" them on Wednesday :-) I am repurposing a lot of my current furniture - I am reupholstering my Josef Hoffmann sofa and armchair - they are currently black but I am redoing in a teal velvet. I am keeping my Chinese Deco Chest (green) and I also have a 1920's arm chair with the same channel upholstering that I am redoing in a pattern that has vaguely the geometric lines of Art Deco - that chair has carved wood arms which I will be doing in a metallic kind of finish because I already had a LOT of wood cabinets in the dining area, kitchen as well as my office area. I am refinishing an Art Deco bar. I haven't definitely decided on a dining room table - because I am also in a condo, I have a small dining area and so I will probably go with a glass top over some kind of Art Deco base. I am refinishing my Waterfall Bedroom set - repurposing the vanity into two end tables. I am not aiming for a full on period style - I think it would be impossible to do on my budget since true Art Deco pieces have gotten way out of my price so it's more of an eclectic gathering of what I like - the pieces I'm keeping I haven't grown tired of for years - I discarded a lot of furniture I had acquired so I just kept those pieces that I continued to want to live with. The dining room chairs aren't true Art Deco but have the lines that I like - these are the chairs that spoke to me immediately after perusing loads of choices online. Chinese Chest from the 1920's Joseph Hoffmann sofa and arm chair that I am reupholstering

Sativa has a good idea for a high contrast design but I might be overwhelmed too much dark black. It would need the balance of lighter floors and the natural light from the windows which could make it stunning. I bought the same pebble tile at our local H H Restore to re do our tiny shower. I want bright white tile like your subway tile but hubby still wants a large format porcelain. The mix from the pebbles can work with many things. Remember when it is sealed the colors will deepen to what it looks like wet. You could use a midtone like the charcoal grout for your floor tile if you are keeping the walls lighter like a warm white, tape or grey from the pebbles. If you go with dramatic black walls, you need a lighter grey ,taupe or warm white for balance. With either color scheme choose a basic floor tile with a bit of texture to prevent falls. A rectified porcelain with touches both cool grey and warm whites and taupes would work with lots color schemes. Keep in mind you may change your style in a few years. So pick a classic with lots of options. It will be easier to change a dramatic paint color than a busy tile pattern.

Since the vanity is between two walls, I'd purchase a cabinet with appropriate filler to fill the entire space, then have a counter templated. I wouldn't want the vanity floating in the hole between walls. Build it in, like the current one is. You can still have open shelving or legs on the bottom if that's what you like.