There's one right answer and then all the rest.
1. Bloodborne
You can argue over the rest now. I'll have a more informed opinion about mid January. I'm still slogging through the witcher 3; I think im 1/4 or more through, I'm halfway through the second city Act 1 Missions, and know there is 1 more city, another Act, and then a final act which Act's 2 and 3 don't seem to be as big as the cities I'm in now.
Then i'll probably try to move on to Metal Gear Solid 5; I really hope that the multiplayer and f2p shit isn't required to enjoy the game. We'll see how it goes but I can't imagine loving the game, I've never liked any metal gear solid games before and have no clue wtf the story is about, so we'll see how the gameplay is.
Then finally I'll move on to xenoblade chronicles, I loved the first one, mainly because it took forever to beat, and was the perfect "podcast" game. That's kind of part of the problem with Witcher 3, your playing for the story and you dont really want to listen to people talk about other shit, but in JRPG's and what was true in the first Xenoblade is i could just throw 6 hours of podcasts on and have to mute them once, maybe twice to get the story bits.
Someday I will get to fallout4 though I don't have high hopes of loving it seeing as I've now tried Skyrim, Fallout3, and Oblivion and didn't like any of them; but people ask me what i want for christmas and this is the type of game that I wouldn't buy for myself but if given as a gift I would try out to see if maybe my opinions changed.
Finally I have Super Mario Maker; this might be the go between of all the other games, if I can stop playing Bloodborne long enough. The problem is A) I've never been the make your own level type of person, and B) There's no real "end" to the game and could see myself trying all the super hard levels and wasting days on them; for no other reason than to prove that I could do it lol.
I'm hoping to wrap ALL of the above up around mid january/late january. There's nothing I'm aware of coming out that really stands out as a must own game, until Dark Souls 3 in March (might be April)
And yes before you ask I OWN all of the games above except for Fallout 4, each of them seem to be 50 - 100 hour games which is both nice, and terrible at the same time.