As far as the pressure goes... Oxygenetics Shower Heads are worth the money. After buying one for the camper, we put them in the sticks & bricks.
We also had low ware pressure problems. Found that the cheapo water regulator regulated too much. Went to an adjustible one with a gauge and we are much happier!
I have also found that if we need to take many showers close together, I turn on bothe the electric and the propane elements on the water heater. This helps the tank recover faster. Otherwise, it is just on electric (when hooked up to shore power).
~ Craig