SCOR-PO-NOK!
I know there's news that it will come out for Earthrise, which I really hope proves true... cos just take my monies!
I personally wouldn't get a Black Zarak redeco, purely because of space (it's the same reason why I skipped LGEX Grand Maximus), but I think that they should definitely do it as a limited exclusive for those who want it and have the room for it.

You know what else would be neat? A Transformer that transformed into Autobot City.
"But Autobot City never had a robot mode!"
Neither did Cybertron until the Cybertron Primus toy came along. And if you only ever want to keep it in city mode, then you can do that. The robot can be a wholly new character.