That's basically it.  Electrostatics only appear to be simple in theory but then again, most don't understand the theory.  Take something like the Stax Lambda, almost all of them share the same housing, basic driver building blocks (stators and diaphragm assembly), cable and earpads yet they can sound very different from one another.  Hell some use the same diaphragm material yet sound nothing like one another.  I blame the turtles....