Welcome to my Yapping. I wholeheartedly believe in this theory, though it’s more of a RANT, so there's a TL;DR at the bottom.
I'm not sure if this theory has been mentioned before, and if it has, I'd love to see the post. This is based on a recent reread of The Stormlight Archive. I don’t have the books with me, so bear with me if there are minor errors.
I believe Brandon Sanderson is hinting at future events in Wind and Truth through the format of the Ketek. This applies both to the historical lore and how the story will end. I'm going to explain how I view this through specific characters.
Kaladin
Kaladin’s story is one of betrayal, which parallels a theory I’ve seen about Honor’s death. Let’s consider The Way of Kings as a Ketek:
In The Way of Kings: Amaram’s betrayal of Kaladin is impersonal, shaking his belief in the status of others.
In Words of Radiance: Moash’s betrayal of Kaladin is personal, shaking his character.
In Oathbringer: Kaladin’s betrayal of himself results in his failure to say the Fourth Ideal. Syl (and Adolin) supports Kaladin despite his inability to speak the oath and his freezing in Kholinar.
In Rhythm of War: Teft’s support of Kaladin allows him to progress to the Fourth Ideal, helping him find his way through the worst of his depression.
In Wind and Truth?
Before discussing Kaladin’s fate in Wind and Truth, let’s explore how Honor died. It’s highly implied, at least to me, that Cultivation betrayed Honor to end the war. This is partly supported by Odium’s statement, “we killed you,” when Dalinar opens his Perpendicularity for the first time. Who else but Cultivation could help kill Odium? This idea, too, can be seen as a Ketek:
In The Way of Kings: Honor is perceived to be alive (The Almighty), but Dalinar later learns of his death.
In Words of Radiance: Kaladin says, “Honor is dead, I'll see what I can do.”
In Oathbringer: I don’t know the middle part of this Ketek, but I think it’s largely irrelevant.
In Rhythm of War: In Adolin’s trial, an honorspren says, “Honor is not dead so long as he lives in the hearts of men!” (Navani says something similar.)
Conclusion: I believe Kaladin will ascend to become Honor. Dalinar may believe Kaladin to be dead—possibly due to Kaladin losing as Dalinar's champion (though I find this unlikely) or perhaps because Kaladin remains behind in Shinovar. This perceived death would mark the beginning of the Ketek, which would then be completed with Kaladin's ascension, making him Honor and thus "alive" again. Furthermore, I believe Cultivation, who may have previously betrayed Tanavast (Honor) to end the war, will redeem herself by supporting Kaladin in his ascension.
Dalinar
Dalinar’s story is one of growth and tyranny:
In The Way of Kings: Dalinar struggles with whether to take the throne from Elhokar (tyranny) while also grappling with his developing morality and the meaningless war on the Shattered Plains.
In Words of Radiance: Dalinar becomes a despot in all but name, taking the throne from Elhokar. He strives for peace but is forced into a final act against the Parshendi.
In Oathbringer: Dalinar struggles with bureaucracy and fears a world ruled by words rather than swords. However, he eventually thrives within this system. He wrestles with his morality and lands in a gray area, unable to forgive his past sins but willing to work towards redemption.
In Rhythm of War: Dalinar relinquishes power, realizing he must assist others in conquering Emul rather than simply retake Alethkar. Though he is sickened by the conquest of another nation, he accepts it as the cost of leadership, much like Taravangian.
In Wind and Truth?
Dalinar will need to complete his redemption arc set up in Oathbringer and, to a lesser extent, The Way of Kings. He will fully relinquish power, likely before the contest of champions. I see him stepping down and naming either Renarin (to mirror Adolin) or Navani (as another Bondsmith) as his successor. He will then battle, possibly as a champion, and most likely fall in battle as a warlord. He will be a fighter at the start of his life and will die as one at the end. Alternatively, he could become the new Odium, fully embracing the tyrant he was in the past, though I find this less likely.
Following CH5/6 we have more proof that Dalinar will step away from power. However clearly he didn't name Renarin his successor but rather Kaladin. Still it shows his realisation he needs to relinquish power.
Adolin
Adolin’s story is one of perception:
In The Way of Kings: Adolin begins worried about how others perceive his father, leading him to consider stepping down.
In Words of Radiance: Adolin murders Sadeas, believing himself unworthy of being as good a man as his father, which diminishes his self-perception.
In Oathbringer: Adolin begins to perceive the Deadeyes as living people, forming a bond with Maya and learning her name. His self-perception continues to deteriorate until he breaks his engagement with Shallan, but her perception of him starts to repair his self-image.
In Rhythm of War: Adolin’s work with the Deadeyes ultimately leads to his success in the trial. He proves himself to be not only as good as his father but better, as he helps the victims of the previous Radiants heal themselves to some extent.
In Wind and Truth?
Adolin will complete his Ketek while Dalinar is stepping down. When Dalinar loses the contest of champions, Adolin will realize that the coalition cannot survive without Dalinar’s leadership. He will find a way to replace Dalinar as Odium’s fused, allowing Dalinar to remain in control.
Shallan
Shallan’s story is one of trauma and theft:
In The Way of Kings: Shallan sets out to steal from Jasnah while dealing with the trauma of killing her father. She eventually becomes Jasnah’s student, stopping her attempts to steal information.
In Words of Radiance: Shallan tries and fails to handle the trauma of murdering her mother.
In Oathbringer: ??? (I’m unsure of this part of her Ketek, but it doesn’t seem critical.)
In Rhythm of War: Shallan comes to terms with her murder of her mother and Testament.
In Wind and Truth?
Shallan’s arc, as seen in a theory on TikTok, aligns with her Ketek. She deals with her murder of Testament by working to undo the harm she caused by retrieving the gem that imprisoned Ba-Ado-Mishram. When Adolin falls, she will again set out to steal knowledge from the Ghostbloods to free him from Odium’s control.
Szeth
Szeth’s story is one of obligation and murder:
In The Way of Kings: Szeth kills a king and is a slave to his duty.
In Words of Radiance: Szeth sows havoc and is a slave to his duty.
In Oathbringer: Szeth frees himself from his obligations.
In Rhythm of War: Szeth assists Dalinar, uniting instead of creating havoc.
In Wind and Truth?
Szeth will work to perform justice, culminating in a parallel to when he was forced to kill Gavilar. This time, he will voluntarily kill Odium, starting by killing a man who wanted to be a god and ending by killing a god who once was a man.
In Summary (TL;DR):
Kaladin dies and ascends to become the new Honor.
Cultivation betrayed Honor and will this time support Kaladin.
Dalinar will step down as leader, lose the contest of champions, and i am confused on his ending but am quite confident he will either die, become the new Odium, or survive without becoming Odium’s champion.
Adolin will replace Dalinar as Odium’s fused envoy to the Cosmere.
Shallan will save the Deadeyes/free Ba Ado Mishram, and then go to steal knowledge from the Ghostbloods to free Adolin.
Szeth will end as he started, killing Odium as he killed Gavilar. (A man who became a god (Odium) vs a man who wanted to be a god (Gavilar)
