I was running a thought experiment some time ago about what could be improved upon in the SA, so I thought I'd let you see my thoughts here as I do have mild Sunlit man spoilers.
WoK:
This one is honestly really good. I'd probably just move the Shallan sections around as right not they are in really annoying locations. I'd also see about giving her more to do as Shallan spends most of the book not making any progress towards her goals.
WoR:
Jasnah's fake death isn't very impactful to the story, and weakens the ending with three fake out deaths one right after the other. We should get some confirmation that she's alive, and probably have her and Shallan speak once she's been transported to Shadesmar. Some of Shallan's dialogue could also be cleaned up a little but that's less of an issue.
OB:
Shallan's breakdown doesn't hit like it should, and her whole character is off for most of the book. Elhokar's death is also done so poorly I didn't believe he was really dead until almost two years later. The fused are also jokes, they need to be shown to actually be capable of serious damage. Dalinar kind of sucked up all of the emotional beats in the story, which made his arc really good, but left almost everyone else feeling flat. Unless Brandon wants Jasnah to be evil she also should probably have talked to Renarin before trying to kill him.
RoW:
The previous entries could all have used a little work, but it's here that big changes start being necessary. Despite the book being about Willshapers and having her flashbacks Venli is a surprisingly passive character. I'd honestly restructure the book, taking several of Kaladin's PoVs as well as most of Adolin's and give them to Venli. She also needs to be more active. I think her finding Kaladin and trying to help him, while also not getting caught would be a far more compelling story than what we got. It would also explain why the Radiants were so willing to let them go at the end of the book. And finally there are some mild inconsistencies between the WoR interludes, and what we saw in the flashbacks that need reconciled.
Kaladin's depression is really mild in its depiction this book. WoK did a much better job with it. I know part of it was intentional, but it still needs work.
Shallan's entire story for RoW is just a poorly done recreation of Dalinar's in OB at best, and an exercise in futility at worst. She spends the whole time saying that no one will love the real her, and I still remember thinking that there was no way the reveal would live up to it. I was right. She spends the whole book worrying about Formless, which was poorly revealed to just be Shallan the whole time. She worries about Ghostblood spies, which never existed. And the Testament reveal was rather weak.
Navani spends the entire book being an idiot. Raboniel was one of the most obvious liars I've ever read in fiction, and Navani still fell for it. I know that more than anything Brandon just wanted to make anti-light but he could have done that without making Navani a gullible pushover in the process.
Dalinar does almost nothing this book, which is really unfortunate.
Once again the Fused are complete pushovers. There were almost zero negative long term consequences as a result of their actions, despite the Fused holding the Tower for most of the book. They had victory in their hands and still managed to lose. None of the heroes died, no one was injured, nothing was lost. Huge letdown. If Odium was smart he would have slaughtered everyone in the tower, or at least have evacuated them to Kholinar as prisoners. Keeping the Radiants alive makes a little sense to keep the spren from bonding someone else, but the humans had no reason to continue to be there.
Additionally just on a worldbuilding side I would have made all of the Fused much more powerful in direct combat. Most of their powers suck, and need overhauled. I've detailed my thoughts on what they should be in other posts, but I'm still disappointed with what we got.
WaT:
Do I even have to say it? There's a lot wrong with this one.
The dialogue and prose needs quite dramatic alterations, as do Brandon's poor attempts at humor.
Kaladin needs a better end goal than just "Help Szeth." Even with Dalinar's instructions I feel like Kaladin would at least try and be more helpful to the Radiants efforts. Brandon even had it set up perfectly for Kaladin to try curing Ishar so Ishar could help Dalinar. He could have even had Wit message Kaladin and say they need Ishar to make a Perpendicularity because Dalinar is stuck in the SR. Either would have given much more urgency or at least more weight to what Kaladin was doing.
Cut some of the needless bloat. Adolin's chapters could be trimmed down a little, as could some of Jasnah's, and almost all of Rlain and Renarin. I know Brandon was setting up for book 6 there, but there's still a lot that isn't necessary.
Brandon needs to stop holding back with the Fused and Unmade. Yelig-nar shows up for the third time in the series and we skip over that like it's nothing. The Azimir sections did a good job of showing how outmatched the heroes are. Narak needed the same treatment, but instead felt rather hollow when they had to retreat.
Some plot holes need filling. There should have been some mention that they couldn't lock the Azimir Oathgate. And Sigzil needed to swear the fourth ideal to get his armor as we saw in TSM. Brandon could have easily done that by altering the point where Sigzil breaks his oath to be him considering that and the deciding to try and swear the fourth ideal instead. Not only would that have been a cooler scene, and it would also have given him the power needed to overcome the fabrial, but it would have let Brandon pull the heartstrings as Moash killed Sigzil's spren anyway.
Gavilnor. Above everything else I hated this the most. Gavilnor was a terrible choice of a champion, and almost anything else would have been better.
But enough of my thoughts, how about the rest of you?