Palpie

Has anyone ever asked Brandon if there were highstorms on Roshar before cultivation/honor came? Would help in figuring out if the source of the Investiture for stormlight is one or both of them or something Adonalsium left behind that their magic takes advantage of. On the difference in this desolation, I think it's because without Honor (and maybe the heralds and KR) there's nothing to bind Odium to whatever rules there were before. So one way or another this will be the final (true) desolation as either Odium wins and probably kills all humans along with cultivation, or he's defeated and driven away to terrorize some other shard world. I don't think rayse/odium will die just yet.

The Diagram didn't come from Cultivation, only Taravangian's increased intellect / deceased compassion came from Cultivation/nightwatcher. She does appear to have given up on Roshar, but there's no reason to think the Diagram was inspired by anything other than Taravangian's super high sociopathic intellect. In fact, if any shard help inspire it I'd say Rayse was behind it as it is weakening the human nations and the efforts to reform the KR. Also as far as we know it fails to make the parshmen/parshendi = voidbringers connection Jasnah made. Surely if the Diagram identified that connection he would be slaughtering dull forms left and right to stop them.

Also didn't it only matter to keep the atium from Ruin after Vin let him out of the well at the end of WoA? TLR wouldn't have released him, probably, he did have 1000 years of ruin's influence messing with his mind, so why destroy a useful and powerful resource.