No, it was because it was in a building that could be easily locked down. The Circle system itself had nothing to do with it. You don't need the Circles to lock down a school.
The Circle places potential Abominations and blood mages away from major population centers thus reducing the number of victims in case of attacks and it reduces the response time of Templars by having them be stationed right down the hall. There is no other system that replicates these effects,
Talk about apples and oranges! More like: Let's ask the city elves how they feel about policing themselves, not how they feel about the humans. I'm betting the city elves would welcome the chance to be out from human rule.
You're missing the point. Humans police other humans which has allowed for crimes commited by humans against elves to be ignored. What guarantees are there that the mages will not simply ignore crimes commited by their own against normal people?
Orsino is guilty of this in DA2.
No, it doesn't. An internment camp should always be treated as a short term solution.
Not if the disease is incurable.
It's obvious that the classroom education that the Circle provides does work, so we can keep the classes as is.
It works so long as we are not expected to trust every mage who attended them to live on their own away from the watchful eye of the Templars.
Fine, the overwhelming majority of the time mages cannot travel without a Templar.
I did want to point out that in the cases of Wynne and Irving, it took pretty much most of their lives before the Chantry let them leave on their own. And even, with those few mages you listed, they are still being baby sat by a potentially murderous nanny; that's what the phylacteries are all about. All it takes is a Templar going, "Gee, maybe that mage is trouble" and tracking them down across Thedas. They don't have to have any evidence or a reason beyond " I suspect blood magic afoot." It doesn't matter how long one has been a mage, or their position in the Circles, they can still be subject to this at any given time.
You are aware of the fact it takes two keys, the Knight Commander's and the First Enchanter's, to acess the Phylactery room, correct?
In order for a Templar to pursue a mage, the FE has to agree that it is necessary. Basically, they keep each other in check.