Well, here is my concern with Amy or Rory... they would break my heart. Because it would make so much sense give that no one really knows exactly how or what the angels do with them... that would give a perfect lead in. But one would want to know where the other was and... the feels, Tereesa. The feels. I still can't watch that ep without turning into a bawl baby.
Donna would be SO MUCH FUN. But... the memory thing. I can't do Jack. Not now. Love Jack, but... with... the thing... with John... and Kate, dammit, I just can't. Fan. For. Life.
Now, Madame Vastra or Jenny would be fun, too. :P For... reasons.