@Dean_the_Young This topic has captured my interest and I want to add a bit more since I haven't really debated here yet....
What if Mother Petrice returned in Inquisition? First of all she would no longer be 'Mother', or 'sister' or anything remotely linked to the Chantry. I'm surprised no one has thrown her in the same boat as Anders for the crap she started and tried using religion to justify it "The Qun is gonna brainwash everyone because no one in Kirkwall has a mind of their own and they will all be Qunari zombies!!" Anyone who views her behavior in DAII as heroic is a fool in my book because nothing she did was heroic she; lied, hid, schemed and she acts like a child caught taking from the cookie jar red-handed when confronted and got all indignant and shifted the blame onto others [Force persuade/Lie] "It was the templar's fault not mine! I had nothing to do with it at all I swears!" She is a liar and a sneak and a bad one at that, even the title of her Act One main quest gives it away "In wolf's clothing" she certainly isn't a sheep in wolf's clothing with that scowl and sneering expression she has plastered onto her face 24/7.
Leliana was a murderess, Zevran was a murderer but I don't recall ever hearing them use religion or politics to justify their actions (the game is simply the game and assassin kills). With Zevran, as sleazy and semi-incompetent as he is at least did not desperately cling to some sort of title or higher power as justification for killing. My point is at least when it comes to murder, lying and cover-ups at least the people you mentioned were semi-competent at it, Petrice on the other hand was a complete amateur and her ends did not justify the means. She did basically what Anders did "Well those Qunari guys are gonna attack sooner or later, better sooner than later for some reason!" By swatting the bee's nest she incited an attack on Kirkwall by the group she was dead-set on vilifying; would they have attacked sooner or later or at all? Who knows? Perhaps if the selfish pirate and the book had been handed over to the Arishok in Act 1 then the attack never would have happened (or at least they would have left Kirkwall for the meantime allowing the Viscount time enough to muster a proper defense and call for reinforcements).
So yea I really see no point in having her out of all the characters featured in DA2, I really can't picture her having anything to do in Inquisition unless she is living the life of an excommunicated pariah, living in squalor in the sewers beneath the city feeding off of rats, grub worms and whatever nutrients and minerals she can harvest from excrement and bile pools. She made her superior and her religion look bad, she's really no better than Anders in Act 3 so I see no reason why a pariah excommunicate like her would even want to show her face among human society. Yea and I don't like her, problem? Am I banned from the story & characters section of the forums now because I won't lick your boots and agree with your vaunted wisdom or that I just plain despise Petrice? Oh right I forgot opinions on bioware forums are translated as "toxic behavior" what was I thinking?