I have a lot of British friends who shudder at the idea of an American actor taking over the lead role on Doctor Who. I’m sorry, my friends, but the time has come. Just as Superman (“truth, justice, and the American way”) as now been immortalized by an Englishman, it’s time for your icon to be reinterpreted by one of us.
However, having the Doctor speak with an America accent would just be silly. Henry Cavill used an American accent for the Man of Steeland whatever American takes over as the Doctor should use an impeccable English accent. With that in mind, I think the best choice would be Michael McKean reprising his This Is Spinal Täp role of David St. Hubbins as the Doctor.
English accent? Check. Wacky persona? Check. Colorful fashion sense? Check. Philosophical outlook? Check.
And he goes to 11.