The Toto Neorest is probably the most luxurious toilet on the market currently. FWIW the top of the line is installed in the Kardashian homes. I am not espousing them as experts who should be devotedly emulated, but they do own luxury homes and are constantly renovating and remodeling with no money spared. You can question their taste but the Neorest is actually a beautiful toilet.

I have the top of the line Toto washlet which has most of the Neorest functionality and my Toto toilet has Connect+ so it is pretty sleek looking as it only has the single hose which is standard for toilets. I believe that the Neorest has no visible connections.

I have been using it for more than 3 years since my remodel and there have been no problems at all. It is completely maintenance free and the wet down function along with the special finish means that it practically cleans itself.

I love my Toto washlet and honestly if you are planning to spend that amount for a toilet I don't think the possible cost of repair would be any kind of significant factor.

ETA A separate bidet wouldn’t be functional for me because I would find it inconvenient to hop off the toilet to waddle over to a separate bidet. The top of the line Toto washiets have a function for the front areas with a wide wash 😂🤫 which is theoretically for female needs. I think the separate bidet is based on older European lifestyies where people didn’t bathe as frequently. If i really needed to hose down the nether regions more than a washlet, I couid just as easily use the handheld shower head in my walk in shower but I am just a vulgar philistine American 🤷‍♀️🤷‍♀️

Seeing how things have changed over the past 60 years and having re-wired or had rooms/ homes re-wired I think I would invest in having conduit placed in the walls prior to drywall. This way when things change, and I suspect they will, fishing new wire will be easier and less expensive.

Put blue tape up and see how things look it matters what side the shower head was on and how high. I put in a long bar that has abiltiy to be low if you are sitting easy to grab or bang on your achy back. Or raise it up to be comfortable to stand under. I would try and keep water supply closer to center but to rear of alcove.

Niche. I put my niches in the rear, and I make them big. Everything has a place and space Bottom for bar of soap that I use a washcloth under to keep things tidy. Top shelf for washcloth storage. Middle for bottles. I put it in the back so it stays dry and out of the line of daily water. Good luck to you, lots of info on this site to comb over. Weed through the good, bad and ugly.

"I see that tray more for soap"

Bar soap set on a flat tray like that pictured would make a mess.

Functionally the showerhead matters more since that's what you'll actually stand under. The wallbar being slightly off-center is way less noticeable than having to angle yourself to get proper water coverage.