Let me leave some random thoughts.
Isn't it kinda amusing (maybe in an ironic way) how quick Urizen dismisses Sparda when thinking about everything he sacrificed to get close to that goddamn sword back in the day?
I love the fact that say adressed Vergil's time as Nelo Angelo and how tough that must have been.
Although they don't really do much with it, and I'm still not sure how his familiars are supposed to work. They are is memory, but independent at the same time. Also strange that they don't merge back with V.
It gives me goosebumps when Griffon says goodbye to Dante, but I don't see how their defeat ends Vergil's nightmare. Maybe in a symbolic way, because they represented that time, but Vergil himself should still remember everything, and it doesn't seem to make a difference to him, if they are defeated or not.
Once I stumbled upon a doujinshi that's quite good and really nailed some aspects of the love-hate relationship the twins have, with nothing inbetween.
It alters the ending of 3 to Dante being able to take Vergil back into the human world. He forces him to stay with him; he is pissed at Vergil for leaving him alone for that whole year between manga and game.
He is the one who can't let go of Vergil and chains his brother this way.
Their life together works a bit for a short while, but Vergil starts to wander around and finally parts ways with Dante. He feels like they don't belong in the human world as the mixed bloods they are, with constantly demons coming for them, what seems like an interesting thought.
Btw - the ending of 5 is perfect for doujinshi bullshit, with both of them isolated in hell together.