Re: Clara and the Second Doctor (spoilers only through aired eps)
I could imagine a flashback scene with her and Tennant being a part of the story. I am liking Clara, and I'm not interested in rehashing old companions. Bringing any back significantly, I'd prefer any from the classic series in some form or other over new Who folks. Nothing against new companions, but I'd rather see some old faces show up before they pass on if they're going to bring past folks back around.
We are quicksilver, a fleeting shadow, a distant sound... our home has no boundaries beyond which we cannot pass. We live in music, in a flash of color... we live on the wind and in the sparkle of a star! Endora, Bewitched