Hardly. Tevinter's issues have nothing to do with it being run by mages; it's oppression and selective law enforcement, like it is pretty much everywhere else.
Apart from the fact Dorian himself says blood magic and associated unpleasantness is a direct result of the mage's struggle for power within Tevinter? The oppression doesn't conjure itself from thin air. It's like that because people with nigh on absolute power are allowed to rule unchecked, and we know what absolute power does to anyone. Mages are humans, with all the ugly baggage that can easily come with it, and possibly exacerbated by growing in a culture that tells you that you're naturally, nay, engineered to be superior to all the mundane plebs, to say nothing of the slaves you kill to make a show for your guests.
That's not saying Kirkwall-esque Circles are the solution, before anyone pulls that strawman out, but ''freedom for all mages forever'' sounds nice and cool until you look north. There isn't much indication that people in the South are generally much better than in Tevinter, so I'm really not sure the South can't turn like Tevinter eventually. There needs to be an oversight, not the Orwellian one that was before but an oversight still.
I mean, with those same arguments, one might easily say that the Templar's issues come from selective law enforcement alone, and ignore the widespread corruption, zealotry and the basic truth that Cole states- it's dangerous when too many men in armor think they're right.