I think there's plenty of rp on both sides; even if those from Gilgamesh maybe aren't as loud as the Balmung ones, there are still plenty of them around! Sometimes all a rp community needs is a fresh injection of new blood, anyways (I say, while secretly hoping more people come to Balmung). Ahem. Really though, whichever server you wind up on, you can't go wrong.
quick edit - also, unless you're going for a very traditional miqo'te of some kind, don't worry so much about looking the part of a fool. With the exception of sticking to established gender roles, even the most different cultures in the world still have common personality types. Miqo'te have become so well integrated into Eorzea that you've got a fairly wide margin for error as far as that goes, imo (unless I missed something, but I've seen a fairly wide range of miqo'te behavior from npcs in game).
quick edit - also, unless you're going for a very traditional miqo'te of some kind, don't worry so much about looking the part of a fool. With the exception of sticking to established gender roles, even the most different cultures in the world still have common personality types. Miqo'te have become so well integrated into Eorzea that you've got a fairly wide margin for error as far as that goes, imo (unless I missed something, but I've seen a fairly wide range of miqo'te behavior from npcs in game).