Damn I really love Astrid´s path even though, right now canonically she´s probably the least important character in the game right now.
The only two paths that seems to be relevant to bigger plot are Nyx/Astrja and given what you discover on those paths, I kind of have a feeling that this game is gonna end up with either MC dead or MC leaving the past with pretty much just a goodbye.
Nyx´s path cannot be that big of a deal, given that its apparent that characters from sandstorm are already affecting English side of conflict, so if I were to guess - its all part of one big loop where MC cannot change anything.
I can pretty much see 3 endings at this point.
MC is dead
MC stays with LI of his choosing
MC leaves all LIs behind but returns to original timeline, probably returning with LI of his choosing from sandstorm
Doubt there is gonna more variants than this, as even in the current state of things, its a cluster fuck of variables and paths.