Jamie(who's a friend so I'm very biased) is probably the most criminally overlooked writer Vertigo had--probably because, except one or two times, he chose not to write the superhero books and stuck to what he does best. But he still is one of the best of the first generation of the "Brit Pack." His ANIMAL MAN was very different from the others but probably the most grown-up. (and Steve Pugh's art was...yum. One of Jamie's best collaborators)
But WORLD WITHOUT END, 2020 VISIONS, OUTLAW NATION--all books that should have received a lot more attention.(the last two are in print and inexpensive, buy them)