The longest-serving Doctor was Tom Baker, in my opinion the best of the original Doctors by a fair margin. Since his stint ended, although he continued working right up to the present (and he is nearly 80 now), he never seemed quite able to step out from under the time lord's shadow. Similar problem with Billie Piper. She has since appeared in quite a variety of drama. 'Secret Diary of a Call Girl' was a brave attempt to break away, but one that I suspect backfired a bit, all things considered. I think it's her face. No matter how she does her hair, or what she wears, she always looks like Rose - and the character keeps coming back.
Christopher Eccleston limited himself to just one series because he was worried about becoming typecast.
Then there is David Tennant. He left the series and went to America, where nothing much happened. Now he is back and his career seems to have been rebooted. "Broadchurch' and 'The Politician's Husband' have put him centre stage again.
My conclusions from the above? You can avoid being typecast as the Doctor or companion, but it ain't easy. I think Matt Smith will go this year for the sake of his career. The Christmas Special, I expect.
Christopher Eccleston limited himself to just one series because he was worried about becoming typecast.
Then there is David Tennant. He left the series and went to America, where nothing much happened. Now he is back and his career seems to have been rebooted. "Broadchurch' and 'The Politician's Husband' have put him centre stage again.
My conclusions from the above? You can avoid being typecast as the Doctor or companion, but it ain't easy. I think Matt Smith will go this year for the sake of his career. The Christmas Special, I expect.

), Amelia, Song For Marion and the forthcoming Thor movie on the big screen