The time for the newest Doctor will hopefully arrive soon. So time to look back.
At the end of Waters of Wars the Doctor began to take a dark turn. He was depressed about his lonely status, he has been prophesied by multiple seers as soon to die, his friends suffering due to his fights and causes, his people are all gone, and he feels helpless, or impotent, to make things right in existence. So he meddles on a major scale, undoing three deaths that had global effect.
Not to plan. And he is afraid of what is to come next. And in his next and last story he meets Wilf again, he has popped again a number of times and
He must his oldest nemesis the Master and his people the Time Lords. A madman and a genocidal species who would wipe out all existence to survive. He stuck between them and forced to choose. And after he does, the Master is left with one as well.
But in the end of the story he pays the price for his adventure and to save the world and Wilf's life. Fatally exposing himself to radiation. But he finally finds a way to take a balance between dictating terms to the universe and being subservient. He takes small steps for those he loves. Old companions Matha and Mickey are about to be murdered, and old friend Sarah Jane is about to lose her son in an accident, and Jack Harkness is lost in a depression, since the events of the last Torchwood story. And then others he crosses paths with. He takes small steps to make there lives right. Such as with Donna who can never have her cosmic adventures back or what she felt and grew into, but maybe he can give her some ease in life and a way to create some new experience of her own, in her own way.
Then he faces his end, grudgingly (And despite what some have said, he wasn't the first Doctor to struggle with his end.
But if you aren't ready for good bye, a tribute.
And here is a preview of new companions and adventures for th reborn doctor.
I'm looking forward to Amy Ponds, a refurbished TARDIS and new adventures.