Just wanted to let you know I loved this. What they did to Donna at the end of the fourth season still pisses me off to this day (I'm capable of holding grudges for a very long time).
This is a lovely look at how things should have played out. Because I don't think it was just being around the Doctor that made Donna brilliant. I think she'd always been brilliant. The Doctor was just one of the few people (besides Wilf) who noticed.
And I love the idea of her ending up at Torchwood. If anyone could find a way to keep remembering what happened from driving her crazy, it would be them.