Dante and Vergil Versus these guys...

1.Kage and Dural

2. D.Jin, D.Kazuya, and D.Jinpachi

3.Ryu hayabusa, Ayane, and Hayate

4.God Rugal and Magaki

5. Kurow Kirishima and demon Hyo

6. M.Bison and Shin Akuma

7. Orochi

8. Gill

9. Donovan Bane

10.Red Armorer

Devil Triggers are allowed, they start the matches an 100%, they can only use the basic weapons, and Dante can use every style except Quicksilver.

Which version of Dante is this?

His best...

Then why even include Vergil, since Dante in Devil May Cry 4 can do anything Dante and Vergi in Devil May Cry 3 plus he can do more.

Yes. He can do anything his bro can including teleportation and energy swords. Though technically "teh uber Dante" happens in between of DMC4 and DMC2.

Off-Topic: Has DMC 2 been retconned, Charlotte?

On-Topic: I say they make it too Orochi, where they put up a descent fight and lose honorably.

Dante with Ifrit\Gilgamesh vs Orochi would be SWEET *insert fangirl whitehaired dream summary here*

DMC2 wasn't retconned exactly, it was put at the end of canonic timeline, so as for now:
1st novel (partially retconned, basically only Enzo&Tony Redgrave things left in canon)DMC3 manga-DMC3-DMC1-anime-DMC4-DMC2

2nd novel was retconned
Anime may take place either between 1st and 4th games or 4th and 2nd.