I see some trait of coldness in this new Vergil like how he was easily willing to sacrifice Kat for the cause if he was kindhearted he would've agreed when he first heard Kat was kidnapped rather than argue with Dante until he decides "fine lets have it your way" and if he was kind he wouldn't say that he would've said "You know what maybe your right" plus when he agreed with Dante he said it in a....errrrmmmm....devious tone like he doesn't care about Kat but he needs Dante on his side like he is using him and plus this Vergil says he is doing this for the sake of mankind but me think he is out for revenge for what the demons did to his adoptive family.
Plus the whole being a millionaire thing is like another reference to Batman/Bruce Wayne....in the morning he is Vergil *insert last name here*, rich & classy millionaire, but at night he is Vergil the Leader of the Order and notorious demon slayer.
He even looks like Bruce Wayne(well one of his many variations from the comics, cartoons, and movies).
I wouldn't be surprised if he starts referring to himself as the "Dark Knight" or the "Dark Angel".