First off, I'm a fan of Brandon's work. And I've met the guy and like him as a person as well. I think his work in the Wheel of Time was perhaps the best of the entire series.
But I'm really struggling to like the Stormlight Archive series. I keep pondering why this is. There are definitely some positives and some big negatives. But here's how it breaks down for me:
Positives:
Jasnah. Great character. Reminds you of Moiraine Damodred (WoT). Competent, thoughtful, coherent, well-written. A bit cold and clinical at times, but that's part of her charm. She understands what the stakes are and puts the mission of saving the world ahead of everything and everyone else. Best character in the series by far. Frankly the books would have been SO, SO much better if she were the main character instead of Kaladin.
Gavilar. Seemed like a really good character that had the potential to be great. Wish we had more time with him.
Navani. Very good character. But sadly there isn't much in the books from her perspective so it's hard to know what she's really all about and what she's thinking about people and events.
Taravangian. The whole devious plot with him and his people is a bit difficult to follow and unwind. But it's still a pretty fascinating concept and it's interesting to watch it play out. Particularly as Taravangian grows to like Dalinor even as he is trying to ruin him.
Alethi. Brandon does a pretty good job of establishing their culture and history in a way that feels real and believable. They may not be terribly likable as a people and their religious beliefs are a mess, but overall it comes together pretty well.
Negatives:
Three worlds. I get what he was trying to do with the Physical/Mental/Spiritual realms. But it just doesn't work. It's not interesting. It usually feels like a distraction and a waste of pages when time is spent dealing with it (particularly the Mental realm and the silly glass beads and inverse land/water layout). It feels hollow and uninteresting and doesn't feel believable.
Spren. They just add so little and take up so many pages. While some of the primary spren (like Syl and Pattern) are actually good characters and more appealing than their human counterparts, overall the concept of the spren just doesn't work (as with the Three Worlds comments above).
Kaladin. This guy is the biggest tool. It isn't often that I find myself constantly hoping the main character in a big series is killed off, but that's where I am with him. He was actually good in the first book as they did the bridge man story. But after he got out of that situation he's been insufferable. His broody, self-pitying, stubborn, emo act is SO TIRED. God just go die somewhere and let Syl find a more worthy human already. The whole bridge 4 crew got old fast after they got their freedom.
Dalinor. Once his background was fully exposed and it was clear what kind of a horrible monster he was for his whole adult life, how can anyone empathize with or root for this guy anymore? Even if "The Thrill" was some kind of spren possession orchestrated by Odium, it just doesn't change what he did. And people might argue that is the whole point of his story arc and how he's growing into this great figure who can resist Odium... and that's fine, but it doesn't change anything. Too much blood on his hands. It's one thing to have a flawed hero. Heck even a deeply flawed hero. But Brandon went too far here and established Dalinor as a sadistic, bloodthirsty, mass-murderer with an addiction to killing. I find that he's really beyond redemption as the protagonist of the series. Even if I genuinely like the person he has become... it's too late for him.
Shallan. I liked her so much early in the series. But as the character starts developing her multiple personalities disorder, she becomes increasingly difficult to like or root for. And is anyone else yet sick of her fawning over Kaladin? Even right in front of Adolin? Or sick of how she disrespects Jasnah constantly? She feels like a character that is the "author's favorite" and gets unreasonably favorable treatment and never the comeuppance that she so richly deserves. So you had a difficult upbringing and have big skeletons in your closet? Get over it stupid, the world is about to end and there are plenty of people out there who were much worse off than you ever were.