Idris Elba's name was circulating the internet's speculation/rumor mill about who should play the next Doctor even before Peter Capaldi was cast as the 12th Doctor, and we still think he would kick the crap out of the role, should he get it. The BBC has taken fire over the years for not casting enough minorities in lead roles, which spurned showrunner Steven Moffat to reveal they had, indeed, offered the role to a black actor at one time, but for an unstated reason, it didn't work out. Of the many talented leading men who could have been offered the role, most fans speculated that it was none other than Elba. There's even a precedent for Time Lords casting off their genders and races when they regenerate, thanks to an episode at the end of Capaldi's second season as the Doctor, so there really isn't an excuse to limit the role any longer.
Elba long ago solidified his status as a leading man, and has had roles in American Gangster, Takers, Thor, Pacific Rim, Zootopia, and Star Trek Beyond, among many more. If you thought Elba wouldn't take on a television role with such a successful career in film, you're wrong. Even after making the jump to the silver screen after The Wire, Elba continued working on the small screen in shows such as Luther, The Big C, and Guerilla, which he will be headlining this year. It's not clear whether or not Elba would take the role, if it were offered to him, since he once said, "I'd look silly in a bow tie," referring to Matt Smith sporting a bow tie for his rendition of the Doctor. He may need some convincing, but if it could happen, the show would certainly reap the rewards. He's already proven he can play a god (Thor), an alien (Star Trek Beyond), and a pilot (Pacific Rim), so if you combine those roles into one, boom: you've got yourself a Doctor.