One way that Rogue One defines itself as something different to the wider Star Wars saga is by the fact that its story focuses on ordinary men and women (and robots), rather than the ultimate battle for good and evil between the Jedi and the Sith. But that wasn't always the case -- and a Jedi almost played a crucial role in the film.
The Art of Rogue One: A Star Wars Story, which came out last week (check out a gallery of artwork from it here) reveals that in early drafts of the scripts Jyn's family dynamics were a little different. First off, she had a brother, but while her father Galen was always going to have had links to the Empire's work on the Death Star, there was going to be another reason the Erso family was in hiding away from the Empire:
Lyra Erso herself was a Jedi Knight, on the run after Order 66.
Lyra still would have played the same role she still eventually did in the movie, dying in an act of defiance against Krennic, but according to scriptwriter Chris Weitz in an interview in the book, the decision was made pretty quickly early on that having a Jedi in the movie didn't fit the approach they were going for:
For a long time in the story, there were Jedi around, even if only in the background -- Jyn's mother was a Jedi. But we thought that it would be more interesting to have a story without Force powers -- without lightsabers.
We could explore a period of broken faith, a galaxy without hope. There's despair because the Jedi are gone -- and with them, for many, even the memory of the Force. We know from A New Hope that Luke Skywalker hasn't even heard of the Force, out on distant Tatooine. That meant our story could be about normal people pulling themselves up by their bootstraps.
Lyra still does have ties to the Force in the version that made it to the big screen; ancillary material has denoted her as a follower of the teachings of the Church of the Force, the same ideological organisation The Force Awakens' Lor San Tekka is connected to. But it's for the best that Jyn was kept far away from the story of the Jedi and the Sith -- that can be safely kept for the likes of Luke and Rey in the mainline movies.