Given that we now have fairies and they have used most of the nature magic ideas, I don't know if there is still a place for elves. But if so, it would be great to see elves of the High Elf / Dark Elf variety since there would be inherent contrast there (like with the vampires and werewolves). With many of the recent worlds being partially a 'real' world and partially a 'fantasy' world connected to each other via a portal or other in-game explained system, this may work for the elves too. As has already been mentioned, dragons and other fantasy creatures could round out this expansion. If this were done in a culturally diverse and neutral way, we could potentially also include Chinese-type dragons here (or that could go into a future Chinese pack), since most people would otherwise assume fantasy creatures and elves would ordinarily fall into more of the European style. I think with these, we would basically have every potentially feasible fantasy / occult being in the game that makes sense (since we aren't going to have larger-than-Sim-sized creatures), aside from perhaps regional / cultural variations of ones we already have (mummies, more types of ghosts, etc.).