you miss the point entirely their end goal is freedom, that's it. rebellions don't start by people having any idea what to do with it afterwards, by leaving the circle they achieved their goal they were free. until the templars went rogue.
people forget the Magi didn't start the war, they simply left the circles. the Templars are the ones who went rogue to murder them all and the Magi have been defending themselves ever since.
Then it's a short-sighted end goal indeed. Freedom is great and nobody can be against virtue, but in practice mages aren't ordinary people and will never get treated like so, not even in Tevinter. You simply cannot go from the Circles to total, unrestricted freedom. That's a completely stupid utopia. And yes, successfull rebellions are done by people who have an idea of what the hell they are doing, unless you like stuff like the Terror in revolutionary France, or, well, the indiscriminate shitstorm that has fallen on Thedas since the rebellion began.
Magi didn't start the war, but Anders did the blast, the Resolutionist were already gearing up for it, and I'm also pretty sure mages didn't just stroll out of the circles on a sunny afternoon, the Templar guardians surely resisted as was their duty. They're not exactly poor defenseless victims in this affair.