That paper actually brings up a problem for using a black Doctor, for the folks that complain about the racism of the show. One of the complaints of Racism levied is about his reaction to Martha being told not to worry about being suspected of being a slave and to just walk around like she owns the place. Well, if the Doctor was black, you'd have that whole complaint magnified tenfold for most adventures set in the past.
I'd be fine with a black Doctor, but, it wouldn't address that concern, if they truly believe it.
One Day I hope to be the Man my Cat thinks I am
Where are we going? And why are we in this Handbasket?