What if the invasion of Naboo didn’t occur until the final act? What if the threat looming over the movie is that the home-world of one of our heroes will be destroyed?
Open with the escape from Naboo, go into Tatooine, go to Coruscant, and go back to Naboo.
It would be hard to explain why they are being attacked by droids and a fleet that hasn’t begun invasion yet.
Think of it like the unofficial war that resulted in the Panama cannal.