Uh, pardon the wall of text. Again. Sorry!
Anders literally killed dozens of people including a Revered Mother and the fans (women especially) give him a free pass.. Solas says he wants to restore the world he messed up, and everyone wants him hanged. This fanbase is all messed up.
God, if I had a dollar for every time I saw complaints similar to this, I'd... well, I'd probably have, like, twenty bucks. But I still see this complaint a lot, substituted with various different character names and various different reasons that "soundly proves" the fandom's hypocrisy.
"Solas lies about his identity and everyone gives him a free pass! Blackwall lies about his identity and everyone hates him! This fandom is so hypocritical!"
"Dorian has shitty opinions on slavery and everyone gives him a free pass! Solas has shitty opinions on the Dalish and everyone hates him! This fanbase is so hypocritical!"
Solas admits to wanting to destroy the world and everyone gives him a free pass! Anders blows up a Chantry and everyone hates him! This fandom is so hypocritical!"
Makes me wonder who this "everyone" is, and how they manage to hold such a wealth of contradictory opinions. Yes, a lot of people don't like Solas, and don't like what he plans to do. But I know a lot of people don't like Anders and what he did, either. I imagine if you compared the number of Solas fans and haters to Anders fans and haters, there'd be generally more positive feelings for Solas, especially since I've seen at least a few people describe him as "Inquisition's Anders, but better-written and a lot less annoying." And there are other factors to account for as well - Trespasser's been out for a few months, whereas 2 has been out for years. People have had time to get over Anders, and since pretty much the entirety of 2 was swept under the rug by the writers, a lot of people have simply put him out their minds. Can't get mad at someone when you hardly think of them - but I'd bet that, if you went back to shortly after the release of DA2, you'd see even more vitriol for Anders than you do for Solas.
(That being said, I've noticed that the reception of DA2 on Tumblr is... bizarrely positive. Nearly every other gaming forum I go to has an overall negative opinion of BioWare in general, and DA2 in particular. It weirds me out every time I get on Tumblr and remember that, oh yeah, people actually seem to like it there. It's even enduring, at that. I mean, look at the Cullen fanbase - it's practically deserted by now. But you can still find new art of Fenris and Hawke and Isabela. It's bizarre. So perhaps that's warping your view somewhat - I can't for the life of me find any negativity about anything in DA2 on Tumblr.)
I think the issue a lot of people have when it comes to Flemeth is that everyone either puts her as a hero or a villain, with not much in-between. I've noticed too that, no matter what alignment they put on Flemeth, people almost always talk about her like she's inevitably going to succeed at whatever she's trying to do.
But in Inquisition at least, Flemeth seemed extremely falliable to me. Her relationship with Morrigan is a perfect example of this - it seems to me like she genuinely believed everything she said to Morrigan. Truly thought that all the abuse she put on her would help her in the end. That she was being a good mother. And instead, Morrigan breaks from her the first chance she gets. Turns on her and refuses to acknowledge any good she did. Says that she'll never be a mother like her. And you can see how that wounded Flemeth.
She didn't want to hurt Morrigan. She wanted to prepare her. To make her stronger. And she just broke her instead.
Solas says that she was the best of the Evanuris, and sincerely wanted what was best for the People. And I believe that. But I think that, like Solas, she was ruthless and didn't always realize the full consequences of her actions. I think she still isn't great at realizing when she's hurting people, at knowing what their feelings are and how they'll respond to her.
She has knowledge and strength and cunning, and I think her power comes a lot from that. But I don't think she's very good with people. It's another reason why I question the theory that she's been manipulating Solas all along. She was "manipulating" Morrigan and the Evanuris, too. Morrigan called her an abusive mother and basically ran way. And the Evanuris straight up killed her. That doesn't scream "master manipulator" to me.
I agree that Corypheus could've worked as he was if they put more effort into writing him. But I think he would've made a stronger villain and character if they also gave him some actual credibility. The destruction of Haven was a wonderful gut-punch, but everything after completely undermined any threat he could pose - even the devs admitted he should've had another victory. And he should've, because he could've been fantastic if he had. He's probably the only villain I can think of who can make the "A God Am I" cliche interesting, because the whole tragedy of him losing his faith and trying, in a weird way, to regain it by becoming a god himself is a fascinating twist on that worn old trope. It drives me crazy that the games didn't properly utilize it.
But I don't see that as a reason to strip him of his credibility either. I think he could've been a real threat and still have kept his tragic motivation. And I think he would've been all the more stronger for it. A toothless villain just drains all the tension out of the story, especially in a video game where you have direct player involvement.
To compare to Solas - just look at the end of Trespasser. Going through the various levels, reading letters from the Qunari on some strange agent that's decimated their forces. Finding corpses of soldiers who have been literally scared to death. Stepping through that Eluvian, seeing the stone Qunari, seeing Solas casually petrify the Viddisala (Who was the main antagonist of that DLC) even the way he holds you at his complete mercy, punctuated by how he looms over the Inquisitor as they bow beneath the pain of the Anchor. To say nothing of how cold and low-key sinister he is on low-approval.
That's threatening. And not even in a direct way, either - Solas isn't laying siege to your castle or holding your loved ones hostage. It isn't a direct attack on the player, as Haven was for Corypheus. But it's a plain display of power. A way for the writer to say "Look at this guy. Look at what he does to his enemies. You don't want to be one of them." Imagine if Corypheus had gotten that treatment, consistently, throughout all of Inquisition. Imagine how much more tense it would've been, every time he appeared. Imagine how well-earned your victory would've felt, when it came.
Instead, it's something you almost stumble into.