I've always written towards movies that take place across two worlds. Most of the movies that I've worked on take place in two worlds, or sometimes three worlds, where you have a normal world and a fantasy world that mix and overlap. I never shy away from the series stuff in the real world. Big Fish is about mortality.
Woody Allen has done some excellent serious movies, too, like Crimes And Misdemeanors. Very overlooked movie, I think, and really his best. And currently I like Big Fish!
A man tells his stories so many times that he becomes the stories. They live on after him, and in that way he becomes immortal.