Could Marvel be going for a new darker look for Doctor Strange, and possibly an R rating? It looks promising with the recent news that Scott Derrickson will be directing it.
Scott Derrickson is currently known for writing and directing The Exorcism Of Emily Rose, and his own concept, Sinister. ( Sinister 2 is also in the works). Not only are these horror based films, take a look at his info on IMDB.
Scott Derrickson has written or helped write Deliver Us from Evil, Hellraiser: Inferno, and Urban Legends: Final Cut. He also directed The Day The Earth Stood Still (2008).
Doctor Strange would be the perfect character for the darker side of Marvel movies. He often fights demons, cults, and other horror type villains throughout his adventures. To many Doctor Strange fans, it would also take a major plot or extra evil villain to actually give Doctor Strange a challenge.
Doctor Strange is often the go-to man for other Marvel heroes in a dilemma involving mystical elements, magic, other dimensions, etc. And since the movie will be produced by Marvel Studios, you can bet it will most likely tie into The Avengers, and possibly the Infinity Stones.