My problems with that scene:
1) Lilith was weak and died with 2 bullets. How is that possible?
Because she was weak, that's why she died so easily. It's like she wouldn't fight Dante directly because she knew she would lose.
2) We didn't even see her true demon form. It was a waste, Lilith is one of the most important characters from hell.
I'm not even sure if she has a true form in the human world. It seemed more like she was borrowing a body looking at the way it was held together with that tightening corset thing.
3) The "cops" had bad aim and missed about every damn shot, lol.
They hit Dante a few times, but that was about it. >_<
4) V for Vergil on Vergil's car! That blue!!!!
5) Mundus was a pussy. His wife and kid died and all he does, is casting a lame power attack?
Lilith wasn't his wife, she was the mistress. The only thing he cared for was his heir. It wasn't so lame seeing as it took out a big chunk of the city. Plus when Mundus did confront Dante, we went totally apeshit on him after Dante wound him up over the death.
6) Time stops and everything freezes suddenly, so you can save both Vergil and Kat.
Not sure what happened there with the slow down, not even sure what it was or how to explain that.
How would I fix it:
1) Keep Lilith being shot by Vergil.
2) Instead of shooting, the fake cops turn into demons, providing a decent battle for both Dante and Vergil.
I did wonder why they did not turn demon seeing as some of them did in the comic. But I think also some were humans who followed the demon cause.
3) After dealing with them, both Dante and Vergil decide to part ways, with the mission focusing only on Dante, trying to get rid of the destruction rate.
Not sure how Dante could do that, if you mean him trying to lessen the damage made by Mundus taking out part of the city. Suggestions?
4) Get rid of the crap car stuff.
Vergil would need to escape with Kat somehow, unless you mean get rid of Dante trying to save them while Vergil is driving?
5) Mundus starts taunting Dante throughout the stage, with menacing messages and traps.
We've already had malice taunting Dante, besides, Mundus was intent on totally crushing everything so I guess he was also aiming to kill Dante using that big attack.
6) About the ending of the mission, Lilith appears again, revealing herself as still being alive and trying to get her revenge for the baby's death.
I don't think she would do that. Look how scared she was in the club after Dante had defeated her spawn. She didn't want to fight him, she just cowered in front of him and promised to do whatever he wanted in exchange for safety. Then in the exchange she looked so broken and scared. If she got a chance to live, I'd say she'd run away and try to save herself. She wouldn't challenge Dante a second time after what happened at the club.
7) You fight Lilith in a vicious battle where she has big claws and eventually assumes a snake form. You woul need to destroy several parts of her body, in order to expose her weak point, a sphere inside of her stomach, the same place that Vergil hit with his rifle.