I'm still uncertain what exactly she is the Prince of. "Roads not traveled" doesn't make sense to me yet. It seems their biggest threat is that her and her followers can't be seen by fate, but does she actually have the ability to rewrite what has/will happen? Not necessarily a paradox like a dragon-break, but still some sort of paradox where she rewrites the future, and thus have an effect on the other games?
Without that ability, the story being a prequel feels really anticlimactic because we know nothing will happen or be impactful.