Mage + Templar pair? How about no. Templar abilities come from ingesting lyrium. Lyrium has proven to be a drug-like substance. Do you want to be shackled to a drug addict just because some people think you can go on a rampage?
For Creators' sake, the Qunari release a poisonous substance in a city and kill hundreds of people and all they get is a slap on the wrist (or not even that)... because no magic is involved.
Sure, teach mages to control their powers... any mage stupid enough not to look for help controlling his powers deserves to become an abomination. And the argument of 'an untrained mage is dangerous to those around them' doesn't really hold weight in a world where many countries take little children to teach them to become assassins (Par Vollen and Seheron? Antiva? Orlais?) I understand that a mage has a greater potential for sowing chaos than a non-mage... but it's just a matter of potential. I've always felt that the Circle approach to mages was a bit like Minority Report. You get punished for a crime you haven't committed and the system is accepted because it makes the rest of the world feel safe.
Very few Circles really acted like universities, not like the one you can set up after Inquisition if you choose the right Divine. Most of them were little more than glorified prisons and forgive me for not accepting the idea that any mage, male or female, has to ****** him/herself out to get the freedoms that a non-mage might possess. (check Vivienne's backstory and get Cole along for the ride for some hints of the beautiful things she's gone through to get where she is.)
A non-mage with Vivienne's cunning might have become Empress of Orlais at Gaspard's side, might have become Celene's mistress instead of her adviser, might have ruled Rivain... I can admire that the woman managed to get to a position of power in spite of her magic but the very phrase - 'in spite of' shouldn't exist. It's like saying, you've become a millionaire in spite of being an expert at designing weapons' systems, biological weapons or an expert hacker. Any of those talents could make one a very dangerous person in our world, capable of doing immense amounts of damage to any country's security and its people, but our societies know how to integrate these individuals instead of trapping them in a no-win situation.