DmC for character
DMC3 for battle
DmC Vergil was a better character compared to DMC3 Vergil in this sense; PERSONALITY.
In DMC3, Vergil was pretty much the "I'm Date's opposite" character. Where Dante was cocky, Vergil was serious. Where Dante was playful, Vergil was business. Where Dante wanted to save the world, Vergil wanted to destroy it. It was the same old bullsh*t that plays out in anime and it's been done to death over and over again. With DmC, Vergil wasn't evil nor did he have evil intentions. He wanted to rule so that he could keep the humans under a watchful eye like a king. He actually wanted to save humanity, but was going about it in a way that was just like Mundus instead of giving humans freedom over their lives. But as the DLC shows, he began to submerge into his lust for power to not only surpass Dante, but to prove that his way was the correct way for the humans to live. After which he was corrupted with power and ended up having a completely mixed view on his original goal and instead created a corrupt empire that he believes is better for humanity.
THAT'S a character. Not that "I need more power" monotone personality that only has one purpose. At least that's how I see it. DMC3 Vergil was just power-hungry. He had no other real characteristics besides being selfish, arrogant, and the token bad guy. Him helping Dante at the end wasn't a surprise at all. That's what all token bad guys in anime do and I wasn't surprised in the slightest by their so-called "unexpected" team work. Please.
Now for battling and ruthlessness in battle, I give that to DMC3 Vergil.
I found DmC Vergil's way of carrying out battles too arrogant. I know he needed to hide his presence so that he's not easily discovered, however that didn't help that fact that he could've taken that tyrant in the Order's hideout with no problem. He could've at least fought it since I doubt that the demon would just go back to Mundus right away since it'd be dead by Vergil. Plus the fact that Vergil was pulled into Limbo and only Nephilim can get pulled in to Limbo would've easily raised more questions for the demon. But it's just a mindless drone demon so I doubt it took that into consideration. And then there's the battle of Mundus where was captured way to easily, and finally the final battle. But I do agree that Vergil wasn't going fully serious with Dante and was just playing with him the whole time until Dante realized that the fight was meaningless. Vergil almost dies, but runs away, only to get more powerful and comeback with a serious thirst to kill Dante. Of course he couldn't have been this in their fight because he still cared for his brother during that time and actually didn't want to kill him. It was only after Dante almost offed him that he became a killer after Dante's head.
However DMC3 Vergil gets it for me in ruthlessness. Unlike DmC Vergil, Vergil in DMC3 had no problem stabbing his brother in the gut to achieve his goals. He had no quarrels with slicing through demons left and right and betraying the people he worked with to achieve power. A lousy reason to achieve power of course, but the power, ruthlessness, and carnivorous attitude was what made DMC3 Vergil more deadly. Like a wolf for it's prey.
In conclusion;
DMC3 Vergil has my vote for his powerhouse ruthlessness and his drive to get what he wants, but is a fail character whose just another Sesshomaru to his Inuyasha. (Dante)
DmC Vergil has my vote on personality and a cunning personality hiding the inner monster inside, but is ass when it comes to being intimidating and is the Donatello to his Raphael. (Dante)