I think one of the great things about the Phantom is that he can be taken in so many different directions, more than any other comic book character I know of, and still work perfectly fine.
It seems to me the major inspiration for the new film will be Nolan's Bat-films, which I am pleased with... I think this film needs to go darker both for audiences to take the character as seriously as possible and for it to distance itself from previous film/TV incarnations. We already have two Phantom films that are light-hearted and sunny, and I really like them both.
However, I think it's time to try something new (with the Phantom, that is) for this film, then they can maybe be a bit original and NOT go the Empire Strikes Back-route and make a lighter, more "fun" sequel. The story about how a guy becomes the Phantom should probably be quite moody, given the nature of the subject (father gets brutally killed, son has to take over his legacy knowing he'll likely die in a similiar manner.
Given it's about "destiny" and what it means to be the Phantom, I hope this is a more thoughtful, deeper film than the 1996 version.
Oh, and Ray Stevenson is so cool. I haven't seen War Zone yet (not released here), but he'd make a great Phantom. If this is about the 22nd Phantom, I'd sure like to see him as the 21st. He's big enough, for sure. However, not sure if anybody would cast him as another comic book hero using a skull mark to scare bad guys.
Clive Owen would be great too, as some have suggested.
Also, I am glad to see Boyle agrees with me that Sylvester Stallone should play Hero, the Phantom's horse.