As a Sirenite I can say we are a nice server, not overly populated, but not barren, you'll always see people on. In terms of what server we are, we are more of an RP server, as opposed Raid or PvP, but you wont have a problem finding parties. Siren isn't a bad option at all.

Also if you come, and join my FC, we'll have another SCH. Please, I'm the only healer... lol