why not let player make there own wizards guilds in wizard 101 and have there own guild building and guilds can fight one a nether in guild battle grounds and the more they lvl there guild the more stuff they unlock for there guild building and unlock more benefit for there wizards
I think player own guilds would be fun and players can have a guild building where they can unlock new items to decorate the in side of it and have guild battles and aver time you lvl up your guild the players in the guild get boost like faster card casting or faster healing or more damaging power to monsters or a boost to get more crafting resources