Given both those changes, an experienced designer would be a good addition to the project. You can, however ask for design help here in a new thread. You must include a diagram of that area of the house that includes the neighboring rooms, has measurements for every wall, window, and door, and shows placement of electrical and plumbing. You will get a lot of ideas and suggestions. Are you keeping the bidet? Will you consider moving the toilet? What is below this bathroom (ie: basement, crawl space, lower floor of multi-storey home)?

First question is always "what's your budget"? Other than the stained floor, nothing appears really wrong that styling won't help. So you may be able to achieve an attractive space without spending the world. See if you can have that terrazzo professionally cleaned and sealed. If that's possible, it's likely the easiest solution and will save a lot over the cost of replacement. The floor tile and vanity are cool neutrals. Replacing them doesn't make much sense unless they are broken. But the paint in there is a warm neutral and clashes terribly. Consider a pale blue or light grey. Consider adding more lighting. Updating the towel bars and existing lighting fixture/fan would help too. Then buy some towels that are a dark version of whatever paint colour you chose. That will add a bit of necessary contrast

Saunas, especially dry ones with far infrared heat, are touted as great for health and for sweating out the impurities that we ingest. Others say that they are good for arthritis pain. If you want to fit one into your home, I say, go for it. Get yourself a self-contained one, cabin style. Put it in your bathroom if you want to, or put it in the basement or in a little-used guest room. I have mine in our smalest bedroom, which we now call the Sauna Room. I have not used it in four years - since the bath romodel next door had me stuffing it full of stuff that needed to be tucked out of the way during renovations. (We also widened all our doors to 36” during that remodel, so every bedroom had some construction in it.) I am not sure I ever really noticed much improvement when I did use it, but I neveer did use it regularly. If you were wanting a more traditional indoor sauna with the bin of rocks and wooden pail of water and wooden water ladel, you might want it in the bathroom to be close to water and for the fan to deal with the steam. But if you are not doing that type, you can put it anywhere. If you go to sell, put it away, or leave it there and show how a small tub could replace it, if you have it in the bathroom. You could even do the plumbing for a tub and leave it in the walls, photograph it with a tape rule, showing its position in the wall so that you can tell buyers the plumbing is already in place. Bring a drain to the general area and measure out exactly where that sits under the flooring, too. Have a box of extra floor tiles to leave buyers if they have to open the floor. When you do weird things to your house, you can have the ”traditional” stuff under the surface, waiting for a new owner to uncover and use it. I did this in our main bath when I got rid of the second sink. The plumbing is in the wall for it, and I have the photos!

I am not sure what to do for mirrors so it doesn’t look odd I'd do large mirrors the width of the two vanities; frame them -- with a frame they don't look builder basic. Smaller mirrors will play up the difference between the two (and are less functional). Also, should we match the shower floor tile to the bathroom floor so it has more of a flow to make the space feel larger? It's not a bad choice. Function dictates that tile IN THE SHOWER should be small -- makes it more "grippy" and safer. Whereas, tile in the general bathroom will probably be larger. I'm guessing, but I'd say stick with 9x9 or 12x12 in the main space ... or if you prefer a rectangular tile, go with something like 9x11. Are you sure you want tile in the main space? I prefer linoleum or wood, which are warmer and softer. I'd consider adding a heated floor while you're at it. Such a nice luxury. Other thoughts: - Where will you hang your shower towels? - Definitely put the shower controls on the shower wall shared with the toilet closet ... this'll allow you to reach in /turn on the shower without committing your body to the cold water. - Have you considered storage IN the shower? Niches give you more storage than those tiny corner inserts ... and you should build in more storage than you think you need. Personally, I'd go with a pony wall between the shower and the main bath ... and would put in a looonng niche that would be hidden from view. Shampoo bottles aren't really attractive. - Where will you place your bathroom trash can? You'll want access to it at both sinks and the toilet. Multiple trash cans = more work. - Will you keep a hamper in the bathroom? If so, where? - Where will you store extra toilet paper IN the toilet closet? Do you anticipate being elderly in this house? If so, consider you may need medical supplies near the toilet; storage would be a plus. - I hate toilets in closets ... but if you're going to do one, I'd suggest you flip-flop this one with the shower space. Why? Because then you could have a window in the toilet closet, where as a window in the shower is always a problem. Water will fight you 24/7 and will eventually win. - In fact, you're covering up your only window ... ideally you'd have that window in the main bathroom. Do you have the option to add another window on the left side? - I personally would skip the second sink nearer the toilet and go with a nice big linen closet. A duplicate sink is of little use, whereas space for extra towels, beach towels, bed linens, extra toiletries is always needed. - Your cabinetry choice looks simple and basic. You'll be able to change the look of the room easily with this as a background. - What will you use for a countertop? White, black or tan seem to be the obvious choices.