I don't remember what the non-legacy RP server was designated as, I think Gilgamesh. But I know 100% for sure that as far as legacy servers go, Balmung was chosen back in 1.0 & 2.0. There are quite a lot of RP guilds on this server.

That being said, our character creation (like so many servers) is closed off right this moment. Hopefully after the maintenance tomorrow some of our congestion will be relieved and allow for more character creation.