I’ve been debating how this could work, as I’d LOVE to see it succeed, and I think it could be cool to swap out Hulk for Sabertooth. Bring back Schreiber, but have him maybe a bit more Mane-ish. He could have been in hiding, or off doing his own thing, since the first X-Men movie.
Instead of the Hulk gang, it can be a gang that are similar in powers to the big two (Logan and Creed), but not as exaggerated healing. Imagine Old Man Logan tearing through a host of younger variations of himself/Sabertooth, having to cut their heads of, pretty much only winning because he has adamantium on his side for the finale where he loses it at the end. Mayhem.
Originally, I was concerned there wouldn’t be enough characters to make this work - or the right ones. But, as it’s picking up from DOFP’s altered timeline you can have it still follow cues from the book and original trilogy (plus The Wolverine movies, DOFP and FC) but playing with them and moving them about as they see fit. So Jean could still go crazy and play Mysterio’s role, or Emma Frost’s. Xavier could fill in for Hawkeye (very different dynamic though).
I think there’s ways to do it, but there’s also a fair few challenges in it. I really want this last hurrah for Jackman, and this iteration of Wolverine, to be a good’un. OML works as an end for the character, and definitely can be.
Then the Younger/New X-men/First Class iteration take take up the mantle and go with it as they see fit.