3. Eddie Redmayne (as The Man Who Fell to Earth)
While Redmayne has already shown us what a dreadful Ziggy he would be in Jupiter Ascending, he did recently win an Oscar for his honest portrayal of Stephen Hawking in The Theory of Everything. Redmayne's performance was refreshingly subtle, and the transformations that ALS have gripped Hawking's body were less impressive than how the brilliant mind reacted to them.
Having said all of that, Redmayne would absolutely crush the period of Bowie's life spent in Berlin, where he pursued visual arts, minimalism and expressionism in his music, and attempted to kick cocaine. This era would make for a fascinating film in itself. The picture of a grand personality brought low and allowed to explore himself would be a great use of Redmayne's talents.