I haven't seen the full cinematic story mode, but here's just my expectations from what I'm reading here
Spoiler, click to toggle visibilty
Felo mentioned that the Ed kid could be the new host for Bison. If anything, he could inherit the style, but I wouldn't expect him to just become Bison yet again. This whole story mode should be about moving forward and putting an end to certain storylines to open others. The psycho power style could remain through Ed, but it would be a big chance to just change the moves rather than just copy the same things, and Ed would be his own character with his own moves, simply based on Psycho power, with, at best, variations of existing moves.
Necalli never seemed to have anything to do with the Psycho power, and was more reminiscent of the Illuminati's style, that's the very reason everybody was wondering what his role would be ever since his reveal. The problem is only that the story started by wrapping up Shadaloo and didn't jump straight to Necalli's arc. So I can easily see a next story arc with him that moves into Gill's ascension, he just wasn't meant to be tied to Bison's arc. And since Capcom will keep adding new characters for the next few years, there's no reason to not expect a new story mode with them - though it might come very late depending on how much time it takes them to animate all that.
If I struggled to the end of my determination, to the end of my way of life with my followers, if the result is ruin, then this ruin is inevitable. Grieve. Shed tears. But you cannot regret.