ADRIEN BRODY as Dr. Stephen Strange MD
He's an extremely wealthy, egocentric and talented neurosurgeon, until a near-fatal car accident causes permanent nerve damage in his hands that goes untreated. Sudden cerebellar tremors impair his ability to perform a delicate procedure on his 153rd patient spelling an end to his medical career. In his private life he'd always experienced surreal hallucinations of the dark dimension and Lord Dormammu, a malevolent spirit who's face appeared on MRI scans of brain-dead patients. At his lowest Stephen reaches a turning point, and pawns all of his worldly possessions to traverse the globe looking in India, Haiti, and Tibet for exotic medicines of the fabled Ancient One to cure himself of these visions.
I feel that all the other actors suggested (Depp, Fiennes, Theroux, Dempsey, Cabbagepatch) would only diminish the character to 1 dimension. Adrien is capable of being Stephen Strange at every point in his life; the egocentric neurologist, the broken wanderer, the Ancient One's apprentice, the Sorcerer Supreme. I suppose those other guys would stand a chance if Strange ISN'T the main character, but if we have to follow the origin from his point of view I'd prefer an actor with some "I'm rooting for you" protagonist qualities. I suggest reading the Season One graphic novel of his origin story, (above image) where its clear the artists based Strange's likeness on Brody.
OLGA KURYLENKO as Morgana Blessing
The best-selling author of occult detective fiction and biographical non-fiction. Morgana interviews Strange with the intent of writing a series of novels based on his life, but ends up getting sucked into a mystical adventure as Strange's main love interest.
Selected for her acting in Oblivion (2013)
AMANDA SEYFRIED as Clea Faltine, ICU nurse
alternative: Emilie de Ravin
CUNG LE as Wong the loyal Tibetan melee-monk
Selected for his portrayal of the Bronze Lion in the Man With the Iron Fists, this kid is gonna be the next Jackie Chan I'm sure of it. A triple-threat of mixed martial artist, Shanshou kickboxer, and now an acting career. Cung Le can pull off some unique fighting sequences and provide unique comedy-relief, but more importantly he's the first actor suggested who is actually of Chinese descent.
ANSON MOUNT as Baron Mordo, a Warrior in contention for Sorcerer Supreme
alternative: Jason Momoa
COLLIN CHOU as The Ancient One
This role requires an actor capable of doing stunts, Chou can look aged with makeup/prosthetics but he needs to be a young man during Kamar-Taj flashbacks.
DONNIE YEN as Kaluu the Betrayer
This is perfect because Yen and Chou are natural on-screen enemies, and both fight choreographers could bring their own pieces of flair to the epic demise of the Kamar-Taj.
JIMMY JEAN LOUIS as Brother Voodoo, Jericho Drumm of Haitian mystics
alternative: Rza
MAYA ARULPRAGASAM as Topaz, the sorceress of Indian mysticism
alternative: Nazneen Contractor
HARALD ZWART to "helm" the project
most recently directed The Karate Kid (2010) and The Mortal Instruments: City of Bones (2013) so he can handle both martial arts and magic/fantasy genres in equal parts.