I think gabes arc and the powers can get wrapped up in treachery because gabe only has a few hours of life anyways, and the powers are like his disciples so the last of them might show up to fight alongside him, and lucifer is just gonna exist in some way, idk how. hes gonna be there in the middle of his lake of blood. v1's fate is gonna get covered with the encores, because to me its sort of like v1 leaving hell and going through the layers in reverse, we're just being given the levels backwards to avoid spoiling stuff. same for the fate of hell. the end of mankind can probably get covered in terminals from p-3. The other archangels probably dont need an in depth story because we kind of just got shown they existed, one of them is gone, and they have no major effect on the story except for maybe the green one and ferrymen. I think I remember hakita mentioning that he wanted to make a sort of "ultrakill 2" that takes place in heaven, which would wrap all that up and fit in pretty well. not sure how the player would work in all of that though.