Now that i think about it my bet is next game wont be Alola because of Z-crystals/moves/power

Think about it: XY introduced Mega Evolution and there was a point where it was signifcant as one of the goals of the game (discovering it and getting the ring) but it wasnt very big as a feature as most of the mega stones were post game.

Then ORAS came out and most of mega stones were actually main game while some of the story involving ME was also in the post game (Rayquaza's lore)

Now in Alola pretty much all of the Z-Crystals are main game and there's a really big emphasis put on getting and using them.

Why would they want to use the same gimmick so heavily twice in a row when they've already established Z-moves so well in the very fisrt game of gen 7?

I feel next game wont be Alola and the Z-moves will be post game