Except any none-templar in the franchise has adored her when they met her. You can have your opinion but the opinion of in-game characters is more important than yours because your opinion has no impact at all where as opinion of the divine does matter. So mention that she is a lunatic in your opinion because you can't shove it as a fact. We have yet to see Fiona commit anything immoral. That said she did no even want total mage freedom but wanted mages to rule the circles all by themselves aka separation from chantry.
She is also the strongest mage we have been introduced to and she is not possessed or something odd like Flemeth and she has been free all her life. This shows how pathetic circles are under chantry control. She has vanquished brood mothers and grey wardens admitted that without her magic they would have failed many of their missions. She also somehow cured her taint.
Fiona is one of the good ones and I always suspected she is an author's favorite, I could be wrong though but there are certainly signs.
1. There is nothing stating she has cured herself of the taint, Many Gray Wardens lived long past the thirty years Alistair commented on which Gaider later stated was just a rough guess anyway that wasn't entirely accurate to begin with. So she is in all likelihood still tainted.
2. There is nothing suggesting that the Grand Enchanter is "by far the most powerful mage we have been introduced to" The title doesn't automatically indicate strength, Her loony fraternity probably just mind controlled the rest of the conclave into voting her in.
3. Yet to commit anything immoral? What do you define as immorality? Do you think treason is immoral? Do you think picking a fight despite it not being the wishes of the majority of your peers to be immoral? Do you think forcing your own kind into a life or death situation for beliefs they don't share is immoral? She's an egomaniac more then a loon i grant you.
4. Gaider hasn't commented on many characters individually as being his favorite and i don't blame him.