Realm definitely reminds me of The Sims Makin' Magic! That expansion pack had an awesome magic neighborhood where you could only buy houses using the magical currency. If they did something like that again, I think that would bring an awesome new dimension to the game.
Though if it is a gamepack, not sure if they would make an entire "world."
Whether they would have different types of witches/warlocks is an interesting related question. Like in The Sims 2 Apartment Life, witches could be designated as having light or dark magic if I remember correctly. That mixed with different realms could provide a quest line maybe?
