I just visited some web galleries of bathroom remodelers in the US, and it looks uncommon to have external shower fixtures. They tend to bury as much of the fixture as possible in the wall. From the photos, I don’t get the impression they are using thermostatic mixing valves. But it’s hard to tell. Can anyone confirm or deny?
I think I might favor external fixtures because they tend to be much cheaper and also more easily servicable.
Even a couple of dollars more for a contractor is a lot when a thermostatic valve doesn’t add any value.
You can get inexpensive tankless water heaters.
You want to open the hot valve 100% until the hot water comes because it conserves water. You want to clear out the hot water line as fast as possible. Turning it to 70% just takes longer to heat up and you’re just dumping cold water out for no reason.