A common trend I've noticed with many One Piece movies. A lot of them have characters from the Roger era as villains. You had Shiki, Zephyr, and Bullet, all of whom were supposedly from the Roger era(albeit only Shiki is canon).
Given how we've had a Roger era Marine, Zephyr, and a Roger era Great Pirate, Shiki, I feel like it would make a lot of sense if we had a Roger era shichibukai as a future movie villain.
One thing that I think would be really cool if Oda did was if he decided to make a call back to this panel, where we first see silhouettes of the shichibukai. As we know, all of those silhouettes, bar the one for Mihawk, is horribly inaccurate. Oda definitely changed his mind on what he wanted the shichibukai to be. However, perhaps Oda could recycle his original shichibukai designs as being the designs of shcihibukai from the Roger era, and have these characters appear in a future one piece film.