Mads Mikkelsen is recovering nicely after the cancellation of HANNIBAL. Having already picked up a role in the Star Wars standalone film ROGUE ONE, Mikkelsen could now be offered a villain role in Marvel’s DOCTOR STRANGE. Ironically, it was his role in HANNIBAL that moved Mikkelsen out of the role of Malekith (played instead by Christopher Eccleston) in 2013’s THOR: THE DARK WORLD.
Chiwetel Ejiofor is already playing longtime Doctor Strange (Benedict Cumberbatch) adversary Karl Amadeus Mordo, though his character has been described as more of an ally in the fist film. That leaves one other major villain role for which Mikkelsen would be just about perfect, The Dread Dormammu. He is an unbeatable foe so powerful that Doctor Strange and The Ancient One (Tilda Swinton in the film) consider it a victory when they can battle Dormammu to a stalemate. Dormammu is to the magic and mystical realm of the Marvel Universe what Thanos is to the cosmos.
As you’ve reasonably surmised, I hope Mikkelsen ends up in DOCTOR STRANGE and that he plays Dormammu. Another prominent DOCTOR STRANGE villain that could appear and be played by Mikkelsen is Nightmare. A character that lives in and rules the realm of bad dreams would be right up director Scott Derrickson’s alley, but so is Dormammu and I’m putting my money there.