Re: X-Men: Apocalypse coming in 2016!
I think Magneto, apoc, sinister and the hellfire club as the most obvious villains, and the sentinels who are created by trask so really we have had all the major villains so far. even cough cough dark phoenix...
My review of X-Men DOFP
Cometh the Apocalypse
and the merry Horsemen
War: Sinister, Death: Wolverine,
Pestilence: Mystique, Famine: Storm before Xavier