5. This spot is often given to Peter Davison, aka The Fifth Doctor. His hiring at the time was somewhat controversial, since he is the youngest actor (besides Matt Smith himself) to take on the part of the centuries-old Time Lord. We’ve got to give it to Davison, however. He did create a complex character and was really adept at portraying the Doctor’s internal conflict. Fifth place it is.

Peter Davison, Doctor Who 50th Celebration
Peter Davison had it tough as the youngest Doctor, but he handled it with grace.