We have a 10' ceiling in our master bathroom. The walk-in shower is the same height although it does have an archway entrance to the drying area and then a turn to the left for the shower. (There is a full-length tile bench and shampoo bottle inset on the wall across from the shower head. The height is absolutely fine, feels less "closed in" and helps with air circulation. We had a glass door installed on the entrance for keeping in a little of the heat but we rarely close it as it's comfortable in there. (There is still an 18-24" opening above the door when closed.) We sometimes close on a really cold morning when we haven't cranked the heat up yet.
The faucets for the shower heads are located to the right just inside the doorway. It works for us and allows you to start the shower without getting wet. I occasionally wouldn't mind having the control right under the shower head but, overall, I like this arrangement.
For what it's worth, we not only have two exhaust fans in the bathroom (one in the toilet closet and one at the other end of the bathroom), but we also have a ceiling fan with a light fixture. Especially with a high ceiling, I won't ever have a master bath without a ceiling fan. That helps with the shower air circulation and moisture dissipation, too.