We know that Kaladin will spend a good amount of his time in this book trying to heal both Szeth and Ishar, we also know that he is aware that the problem with the Heralds is supernatural in nature. Perhaps Kal, with Szeth's help will come to the conclusion that Nahel Bonds are the way to heal the Heralds.
We know the minds of Heralds become clearer when oaths are spoken, this is the current plan to give Ishar a moment of clarity when Szeth completes his 4th ideal, and probably when Kaladin speaks the 5th
We also know Nale is the only Herald that joined his order of Radiants and he's also the one that seems the most okay. Ishar is insane, Kalek has battle shock, Taln is unresponsive, Ash has issues with her image, every single one that we have seen is not at a 100% except Nale? I mean, looking back I can't think of a moment where he wasn't logical. He conforms to his ideals and respects the Law, his belief that Radiants would bring Odium back seems unfounded but it might not be, Eshonai seeing Kaladin Surgebind did initiate the process of the Everstorm, and his reason at joining Odium, the singers, and following the only god around, is also logical, we've been attributing it to insanity but it might just be his thought process. He was on the battlefield against the Radiants regularly for a year right? And are we to believe that not one Radiant spoke an oath near him giving him time to reconsider? at the very least he seems the one that is least suffering from mental ailment, perhaps that is because of the Nahel bond. If speaking oaths around Heralds heal them, what about them speaking oaths?
We've assigned Ash as a Dustbringer thanks to the POV character list, so she is most likely going to get a bond soon and Taln would be the only non radiant on the list on POV characters, he has the right powers assuming he gets back/maybe still has his Honorblade, but everyone else is or should become Radiant, so him bonding a Peakspren seems likely to me.
And, we might have a peakspren floating around looking for a bond. Peakspren hide in stones and Kal has a random stone in his pack, something that could have to do with Fortune and Connection thanks to Dalinar or it could be a peakspren in disguise. The quartermaster is suprised at the rock but not the horse afterall, and Tien never handed Kal the rock, only the horse. Kal is on a journey to heal a hearld, what if, somehow, Taln ends up at Shinovar with him and ends up bonding the Peakspren that was trying to (maybe)bond Kal instead
Thoughts?