First and foremost, would I buy FF XIV for XBone? No, I have no interest in the game.
As for why I buy RPGs, I get them for their depth. A lot of games (at least pre wii/xbox360/PS3 time frame) didn't have very much customization. Changing weapons, armor, skills, magic, ect was pretty uncommon in most games, and even those that did have those things it was very limited.
Also as far as depth is concerned, the stories and adventures have always lasted the longest (as far as completion times). I get tired of buying a game and being done with it the same day (a real problem in one of my other loved genres: fighting). I like games that will scratch my gaming itch for a few weeks, not a few hours. That even holds true today.