TBH, sounds like it would be a lot more straightforward (and cheaper) to just install a scandinavian-style wetroom and either fit a power shower or buy a cheap car pressure washer.
Apart from the sealed light fixtures and the slightly excessive height of the kerb/curb, that sounds a lot like the bathroom I had as a kid in Norway, which was nothing particularly unusual. Get the tiling and colours right and it would look just fine.