So many people hated Donna's ending, and while i certainly didn't like it in the sense that obviously Donna dserves better, I think the fact that it's so heartbreaking is just evidence of how good it was. If I were Donna give the choice, would I want to go back? Probably not. But if I were the Doctor, would I do the same thing to save someone I loved? Most certainly. So I can't really blame him, and I wanted to give him a chance to explain himself -- and since the Doctor doesn't lend himself to introspection that well, I figured Handy and Rose were a fair substitute.

I think this older, more mature Rose would feel the burden of being the only one close to him in a way that s1 and s2 Rose never did, because for all that she worried about him I think she revelled in the attention. Rose was always very hyper-aware of how alone he is, probably because she first met him as Nine, and I think that would worry her a lot with this new Doctor, at least until they get well and truly settled in Pete's World.

Thank you!