I wonder what M Night Shyamalan or Christopher Nolan might do with DS?
To echo Claude, M would no doubt put himself in the movie in a cameo, which I personally wouldn't mind so long as it didn't detract from the movie or essence of DS. For sure he'd add some red symbolism as well (LOVES to do that in his films for some reason) but unlike the WB pilot it would be subtle.
I like Curran as a possible director as I too like HP 3 as the best of the 5 so far. That said however, one thing he did to the HP franchise that I do NOT like is he totally changed an essential componant in the form of HIS vision of Dumbledore. I realize of course that Richard Harris had died and Michael Gambon stepped into Dumbledore's pointy wizard shoes, but to so DRASTICALLY alter his appearance is something I still have a problem w/after 3 films w/Gambon as the wisely headmaster of Hogwarts. Now don't get me wrong, I think Michael has done a FABULOUS job as D and I can accept him w/no problem in the role, but I think his appearance (i.e. choice of costume) and personality should have remained as Richard played it, if nothing else for continuity. I also believe that Harris simply LOOKED like D, at least how *I* pictured him when reading the books.
How does this all relate to him directing DS, well, I'd be afraid that he's decide to ditch something about Barnabas' (or another key character's) appearance. For example he may decide to ditch the wolf head cane, or the ring, or the Inverness etc...If he came in and did something so out of what WE as longtime fans have come to accept, expect and CHERISH about Barnabas, that would ruin the film for me.
Just my 2 pesos...