I think it's time they open up their stuck minds and carry the large map sandbox multiplayer concept to something different than a zombie apocalypse. DayZ is one of the few games these I really loved just because it presented a style of gameplay which offers so much possibilities. The always present threat of other players of which you won't know how do will react to you creates such an awesome atmosphere. In my opinion DayZ doesn't actually need the zombies to be awesome. I'd love to see this in a Western setting with an extensive bounty system for example. Where being a baddy is going to make people hunt you and all out shoot on sight is not the best way to behave. Also with A.I. towns with robbing banks, stagecoaches and trains, shops and so on.
DayZ meets Red Dead Redemption meets APB, would be a damn fine game. Fuck zombies. Otherwise a Medieval setting with large map sandbox multiplayer, but a certain someone is already planning on doing that.