Aww! I'm disappointed that you erased all your character thoughts. I actually agree with you about Ammon Jerro being Loghain. I forgot about our brief Wardens that show up. That was an accurate character write up.
One reason I didn't choose Leliana is because of her faith crisis and ruthless pragmatism in DAI. There isn't really a better fitting character than Cassandra since no one else is really as religious as she is, which is a big part of Kaelyn's personality. She IS the embodiment of good, and follows Illmater, the god of martyrdom and endurance in suffering. Might as well say the Divine is Kaelyn, lol. Or even the spirit that embodied her.
I'm thinking dead whispers Myrkul is Corypheus since that jerk is the one who unleashed the Mask to begin with. He might be dead (Blighted) but he can still gain influence, followers, and make a severe nuisance of himself to a Knight Captain who is just trying to put things back in order and go home.
Oh, you read that? I'm sorry. I was really embarrassed because I realized while written that I had forgotten a lot of details about the game, and didn't knkow many to begin with because I hadn't finished it. (A virus destroyed my computer halfway through MotB, so replace my whole software, which meant I had to reinstall NWN2, then replay Original Campaign and MotB all the way through. At the time I thought, "No! I can't face this!" then not too long later discovered DAO, then that consumed me for years.)
I still stand by how Ammon Jerro reminds me of Loghain (old, grumpy former hero who turned to ruthless measures to fight the impending darkness, acted as an antagonist to the PC since he worked against them, has a humanizing grand/daughter, can become a grumpy ally who stands by the decisions he knew were morally wrong if he joins, etc) and Gann reminds me of Zevran (handsome lech with emotional intimacy issues connected to his mother's death) as well as Solas (that dream-walker and spirit befriend), but my reasons feel too shallow and obvious.
I wish I could comment more on the others.
However, you give really good reasons for why you think each character is who they are, so I stand by them. =)