A suggestion, when trying to please all showerhead preferences by the members, is to use different showerheads in different showers. Also, according to Ferguson, by using a thermostatic control valve it is possible to run an overhead, fixed and a handheld sprayer either at the same time or separately without affecting volume, pressure or temperature.
Showerheads have filter screens and water restrictors which limit the amount of water to 2.5 gallons per minute or even less. It is important to check the flow rate when purchasing showerheads. Note also that the filter screens and water restrictors can clog. Without them the flow rate would increase up to 4 or 5 gallons per minute depending once again upon the pressure and volume.