In DoFP there were many "factions"...
There was the future X-Men (Kitty, Bishop, Warpath, Iceman, Sunfire (I mean Sunspot), and Blink.
There was Xavier, Magneto, Storm and future Wolverine.
Yes, they came together, but at first they were separate "factions".
There was also the Sentinals, which as the initial main antagonists would have to be considered a "faction".
In the past there was Xavier, Beast and Wolverine; and I guess you could add Quicksilver to this for the small part he had.
Mystique was also her own "faction".
And so was Magneto, especially since he broke from Team Xavier and did his own thing.
And of course there was Trask and the government, which would likely need to be considered a "faction".
So in the end, DoFP, had upwards of 7 different "factions".
So the idea that in this Apocalypse movie we'll have:
1. Apocalypse and his Horsemen.
2. Xavier and his new X-Men.
3. Mystique and possible her own group (maybe with Wolvie).
and 4. Magneto (with or without a group).
Is very possible!
And I think there must be an obvious plan for Raven in regards to taking Wolverine. Why go to all of the trouble otherwise. That means that most likely whatever that plan was will be shown in this movie. So asking the question, and speculating, as to why she took him, is a very logical starting point to trying to figure out this movie.
So, in your opinion, why did Raven take Wolverine?????
How will Wolverine get his adamantium back (or will he not?)?
Where will Magneto be at the start of this 1983 set movie?
Where will Mystique be at the start of this 1983 set movie?
What about Quicksilver? Will he be on his own? Did he join up with Xavier? Did he join with Magneto? Did he get lured by Mystique? Will he not be in this (what a waste if he's not)?
These are very fair and logical questions that are the foundation of what this movie is likely to be!