Gaiman has shown an interest in the Man of Steel and could probably do a good job (but the Sandman series was really his adaptation of the Weisinger era Superman, so there's nowhere for him to go that he hasn't all ready gone).
Can you please elaborate on that? I´ve never read something along these lines from either Sandman fans or Superman fans, and I´m very curious. I enjoyed Gaiman team-up Superman/Hal Jorndan special...
I first started seeing the similarities during "A Game of You" where some alternative version of Bizarro Superman is mentioned and shown.
Once you start looking for them, the parallels seem to be everywhere.
First there's the Sandman himself--Morpheus--who is super-powerful a la the god-like (sometimes) Superman. He has girl friends (and problems with a few who pester him and go through transformations--and at least one from his past who is a great regret). And he has that kind of noble, weight-of-the-world aspect that Superman had.
There's a vague feeling of a world that Morpheus came from that is now gone.
He has a "Fortress of Solitude"--with many souvenirs of his past adventures inside it--including a bottle city. The Dreaming itself is a kind of Phantom Zone.
Superman had his cousin Supergirl to turn to and talk to, Dream has his sister Death to turn to and talk to.
There's a legion of super-pets in Superman and super-familiars in Sandman.