replying on topic here and not to a particular post...
i just haven't been able to bring myself to do it yet. don't get me wrong, i totally get it. being pro-mage doesn't make a girl anti-templar, no matter what's going down in the game. i can totally justify it in my head, even for a mage Hawke. but it just hasn't resonated with me. for me, it's not a question of right or wrong. part of what makes the whole thing such a mess (and makes all the fans just like, "FLAME ON!") is that they both have really good logical and moral justification for what they do in those moments before the final battle begins. so it just comes down to putting myself in that particular Hawke's shoes.
i have one Hawke who's a mercy chick. just can't condone condemning the innocent along with the guilty. which is what annulment does. even if it's to prevent innocents from dying down the line, it immediately wipes out all or most all mages in a Circle, innocence or guilt be d*@md. plus she's a mage, so... i imagine she feels some level of regret over the whole thing, but wouldn't change it. but that's hypothetical.
my rouge Hawke just thinks that the whole system is broken, period. she tried to stay out of the whole thing. and she's constantly annoyed when people can't just solve their own problems and just let her chill at home. but she's standing there staring at a Circle-Mage Bethany, so it's like...hmmm? yeah, that tips it to the mage end. (Of course, we know you get the option to spare her, but Hawke f*ing doesn't, so that's how I play it!)
i tried playing an anti-mage or even pro-templar Hawke, but it just doesn't sit well with me. i feel like too big a hypocrite. i'll get it done eventually, just to be an achievement ****, but to answer the main question, no, i don't feel like it's the right thing. feel being the operative word.