The transition from 2d to 3d was always going to be pretty big, I don't really fault them for thatXY, for all its faults, feels pretty complete
The Powerplant is the only thing that feels off to me, and ofc the fact that yeah Zygarde never got its game
The scope doesn't seem that large until you realize they had to 3D model every single Pokemon for this game to ship lol
With that out of the way, I always feel like it's kind of a shame that XY never really made the most out of the mega evolution gimmick, setting everything else aside (because I have a lot to say about XY) that was its single biggest fault (literally none of the major bosses except lysandre at the end use mega evolution. rip)
that is probably the single biggest factor for why the game feels incomplete to me, anyways
I could personally delve into my grievances/criticisms of X/Y but that seems more apt for a different day; regardless, something tells me more kalos mons and more mega evolutions were in the works and then got cut (and that's not talking about the plot/lore elements for kalos, if any)
looking forward to the discourse once we reach that part of the Big Leak