I am not grateful. I hope a talented writer who is a DMC fan gets job to write script for a Vergil or Trish game.
A writer that tries to repair the damage that exists within the story, and will try to explain to us why Vergil acts like he does.
I am no writer but i thought of a way to explain why Vergil is so obsessed with power (DMC 3 Vergil that is):
The night Eva was murdered, Dante refused to run away, but Vergil didn´t hesitate much.
He trembled in fear, and he ran away like a coward.
Then later the demon that killed Eva tracks him down and taunts him and takes Vergil pride away. The demon has the corpse of Eva with him, and he makes taunts like "Look at what i did to your mother"
"Your the momma boy out of the two sons of Sparda arent you? Your mother must loved you alot"
the demon licks Eva´s corpse and continues "Are you not going to save your dear mother boy? Attack me."
With fear in his heart he attacks, but the demon taunts him again by stepping on Vergil´s head.
The demon throws away Eva´s corpse. And tells Vergil "I will let you run away".
"Do you want to run away?"
Vergil is no match for him, the demon is to strong.
Just a idea i have. I know DMC3 manga makes it look completely messed up, but i tend to not care for manga.
Anyway, enjoy this video: