Since 2017 is just a few hours away I figure I post some predictions for the series I read.
One Piece
The current arc will end In July, Pudding and Sanji's Dad are the big bads of the arc and Big Mom will escape this arc and will be the main villain in a few arcs from one, Jinbie will join the strawhats by the end of the arc, Reverie will be 10 chapters long and will focus on Vivi and give us some major world building and development that will set up the final arc of the series (this is years away though) which will cause Vivi to reunite with the Straw Hats, and Wano will be begin in the Fall and take most if not all of 2017 but it won't be nowhare near as long Dressora.
My Hero Academia
Class A's first year will come to a close, the traitor will be reveal and it is Kaminari, we will get quite a bit more about All Might's Backstory and see what is relationship with his mentor was like and find out how she exactly died and of course get a bit of more glimpse into Tomura's past. and Bokugo will continue to subvert my expectations of him being Sasuke 2.0.
Hunter x Hunter
Togashi will come back this year and we will at least get more then double the amount of chapters and maybe if he can go like 40 chapters another Phantom Troupe member will die and this whole subplot of the Princess will be mostly wrapped up.
Also Masashi Kishimoto will debut a series in the summer and will be a sci fi series and be monthly.