I just hope we see a Extra Warriors set or two, since Zuban, Signalman and Rio don't have keys yet, as well as to get DX versions of Dekamaster, Mele and the like.
Ideally....
RKS Extra Warriors
-Signalman
-Zuban
-Rio
-Mele
-Kuro Kishi
RKS Extra Warriors 2
-Dekamaster
-DekaSwan
-Wolzard Fire
-MagiMother
-Princess ShinkenRed
Not counting Gokai Silver or the guys who were in key set 5, the 6th rangers would fit perfectly into two key set releases too. A bit too perfect, if you ask me, assuming they stick to this "2 key sets a month" schedule.