I'm interested in fantasy, and I'm interested in Total War. But I woldn't buy a fantasy Total War.
Let these fantasy games be made by modders. By people who care about both the game and the fantasy source (may it be Warhammer, Asoiaf, Lotr). CA has incredibly managed to "fail" on a "real" setting in Rome II; if they start to make fantasy games, who knows what rubbish would come out...At least modders really care about the setting, and do their best on it.