2. 1989-2005
Now it's not really about what happened in this period as much as what didn't happen. These are the years between the cancellation of the original run of Doctor Who, and its revival under Russell T. Davies; they're known among fans as 'the wilderness years'. There could be a story about some hideous monster that secretly inflicts pain and destruction on humanity throughout the time that the Doctor was off air, and turn the episode into a metaphor for the show and its relationship with the fans. If Christopher Eccleston was ever up for a return, it could finally reveal the circumstances of the 9th's arrival on Earth in 2005 through another character's perspective at the end. It would have to be a very tongue-in-cheek affair, but the writers have proved to be up for that before, and I reckon it could work.