I agree, and by the time of Age of Rebellion, most of those worlds would have been subjugated by the Empire. However as I want to set my campaign 2 years after Order 66 came down, I would suggest that there will definitely be a lot more systems that wish to oppose the Empire's rule, the majority of which would be in the Outer Rim. However, as the Clone Wars were fought primarily in the Outer Rim, there are definitely a Clone Troopers out there which means an Imperial presence exists.
As a side note, does anyone know what happened to the Clones after the Clone Wars ended? Were they all called back to Coruscant, or were they just left out in the Outer Rim until they were "retired" by Imperial citizens who flocked to the Empire's recruitment drive?
Back to my point. The campaign will focus on the same themes as Edge of the Empire. The Clone and the Padawan have joined the smuggler and his/her crew (whoever they may end up being) and are hiding out in the Outer Rim. A least at the beginning, the story will be about doing jobs for local Crime Lords and Crime gangs and build from there. Eventually the Empire might show up (as part of the Clone or the Padawan's obligation - hilarity ensues. When that starts to happen more often, the heroes will be approached by people who claim to be independent merchants and the like, but in actual fact will be a Rebel cell which will lead into more links to the Rebel Alliance.
I ran a 7 year Star Wars campaign dealing with Edge of the Empire, Age of Rebellion AND Force and Destiny type adventures, so I don't have a problem with creating stories around adventure and campaign themes - its the getting used to the mechanics of the game and the different style of play (i.e. working in threats and despair, advantages and triumphs) that I need to get my head around.