I'll admit I'm not a big comic book geek, but I think the incidental placement within that universe, with its decades of existing material provides a really interesting opportunity for Gaiman and other writers to synthesize all of it into a sprawling cosmology. It certainly helps that DC as a rule isn't as insistent that the stories in the universe be tightly bound together as Marvel is, in my experience.
I'll admit I'm not a big comic book geek, but I think the incidental placement within that universe, with its decades of existing material provides a really interesting opportunity for Gaiman and other writers to synthesize all of it into a sprawling cosmology. It certainly helps that DC as a rule isn't as insistent that the stories in the universe be tightly bound together as Marvel is, in my experience.