Re: Shower moisture
maybe use a bilge blower as a 12v exhaust fan.
I have a hvac vent in the head but I leave it closed except when I come in from the heat to spend some time in there.
I personally never have any problem w steaming up but when I shower on the boat I don't use any warmer water than I have to and I only run it just long enough to get wet, soap up, and then run just enough to rinse off. I don't keep shore water hooked up but rather just top off the tank every few days..... Having a hose hooked up is one broken plastic fitting away from sinking a boat OR you have to constantly turn it on and off.