Blackthorne

I'm curious what do you find curious about it? To me it seemed like the natural next step for them. Even under Odium's corruption every Herald we saw (except perhaps Battar) had moments of clarity where they expressed their regret over abandoning the Oathpact/Taln. Even their actions, as misdirected as they may be, were oriented towards stopping Odium/the Desolations. The Heralds fought this war for thousands of years, they endured torture for it and even under corruption most (likely all) of them are ashamed of their actions. To me it makes perfect sense that they'd take up the call again now that the corruption is lifted and Odium is stronger than ever.

I agree with the general sentiment of the OP but I do think if you read it it isn't very clear that Kaladin is all that effective in his approach. Ishar/Nale only start to see clearly after Mishram is freed and Dalinar gives up Honour/Retribution forms. We've seen in past books that Heralds do have moments of clarity that have nothing to do with therapy, so I think the main takeaway here isn't that Kaladin succeeds but that the corruption that impacts the Heralds weakens at the end of the novel. It's Ishar who persuades Nale to try again, Chanarach/Ash change course on their own accord, and the other Heralds also choose to show up on their own. Kaladin's approach is effective at calming Nightblood, but that says as much about Nightblood as it says about Kaladin. Szeth's journey is more complicated, but I think seeing Nale/Aux/Ishar fail to live up to their reputation is part of what motivates him. Generally though I do agree with you, something about Kaladin's whole 'therapist' arc just seems inorganic. I feel similarly about Jasnah and Taravangian's philosophy disputes. So much about Roshar is so different than our world that it seems strange to just inject our practices/beliefs onto the characters. You can believe core concepts liek consequentialism will exist, but the approach/finer details of something like Therapy shouldn't be so similar. This should be even more true for the Heralds as they should have an entirely different set of beliefs than Kaladin. Though actually in this regard the Heralds are all pretty extraordinary in their willingness to fight again.

Reading your comment has really helped me identify something that bothered me throughout the latter half of the book. I totally agree with you on Nightblood/Ishar. Sanderson is careful enough to not have characters do things that were technically impossible based on earlier rules, but the rules definitely feel far looser in the latter half of the book. Nightblood in particular functions as a Deus Ex Machina that is quiet for most of the book then in the moments it's needed the characters seem to remember it exists. An additional problem that I felt with this book is that it has just become hard to believe information is lost so easily in the Cosmere. I can buy that the Lord Ruler was able to impose a top-down suppression of information on a portion of Scadrial, but it just seems unlikely that the Shin can maintain such a vastly different understanding of human history than the rest of Roshar. There are portions where Brandon is clearly trying to show why characters don't share information. For example it seems like Hoid was very active on Ashyn which led to a terrible outcome and Vasher has good reasons for not wanting to share his knowledge, but it just doesn't work for me in other instances. I just feel like at some point Dalinar/Navani should've rounded up all of these suspicious individuals (Szeth, Nightblood, Zahel, Wit, etc.), put them in a room, and asked them to tell them everything they know.

I maybe wouldn't say that he's totally faking it but I do think Harmony knows/plans more than he lets on and that he's more ok with the way things played out than other characters seem to think. None of the shard holders seem very capable of directly acting, in that way all of them are kind of impotent when you consider how much power they hold. However they all seem to be more knowledgeable and have more plans than it appears on the surface. Think of Cultivation on Roshar, who from the perspective of our main characters seems to just be doing nothing the whole time but was scheming and successful in killing the vessel of Odium. I imagine perspective also matters here, shards act on very long time lines.