Cross promotion is a great way to introduce fans of one IP to another. In the case of Berzerk, it's a great anime that decently ties into Diablo thematically.
However, making a F2P game that blatantly caters to whaling just for the sake of giving an open checkbook the ability to roflstomp in PVP is bad for the game as a whole.
Cashgrab while you can if you don't plan on running a game long term I guess.
