The Answer to the question is River Song. Clara can't fly the TARDIS, not well anyway. The Doctor seems to have lost his memory. Who do you call? River! She can fly the TARDIS, The Doctor has yet to give her his Sonic Screwdriver(and he's due for an upgrade anyway), and we have never seen a real relationship between the two of them. Alex and Peter are more age appropriate then Matt and Alex. The former seemed kind of cougar-ish. Clara knows that she can contact River via telepathy and a trance but I am willing to bet the TARDIS has a quick set button to the Stormcage where River is being held when she is still alive. I read somewhere the Moffat is unconcerned with paradoxes.
I think that once the TARDIS arrives at the Stormcage the doctor falls into River's arms and they kiss passionately and in an almost reverse of Sleeping Beauty, The Doctor's memories are waking up instead of him. Clara suddenly feels an outcast, a third wheel. But River pulls her into their wacky adventures which seem to border on the more wrong side of justice. This will happened because Peter Capaldi is not only the 13th Doctor but... THE VALEYARD! Moffat has made mention of a limited run at the Doctor role. Perhaps as the Valeyard and River they find another way to rescue the Time Lords who grant the Doctor more lives. The Doctor could then regenerate when Moffat felt ready to make us cry again. When ever we get settled with Peter Capaladi as the Doctor, I assume.
Of course these are just guesses. We have to wait. Till next September or October, if rumors are right. Where did I park my TARDIS??