For one, they're going to have to cut out the part where he impregnates the daughter of a politician with her gay brother's sperm then bobbytraps her womb to prevent an abortion.
Yes, that is the sentence I wrote there.
Probably not very. He's a lot more critically acclaimed and well respected than Millar, and regularly churns out hit comics that sell a ton and add to his rep. While I'm sure he wouldn't mind more money and wants some specific projects from being adapted, it's not like the people who want Nemesis were picking it over WE3.
I think they could both be a lot better if they dropped the shock stuff. In no small part because it's no longer shocking, there's lots of that kind of thing.