The first time through, I completely missed Jasnah and Shallan seem to already have their plate. There is a scene where a guy gets thrown through the air, into a wall. When Adolin rounds the corner, he sees Jasnah there, with geometric shapes around her disappearing. Then, when Jasnah goes up to Shallan after the Lightweaver army scene, she grabs Shallan's arm, which causes the Shallan lightweaving to puff away. Radiant is the real one of the three. If you remember at the beginning of the fight, Radiant is in full shardplate.
Sanderson has said in interviews that Shallan is an Ideal ahead of Kaladin, so I think we can assume she can summon her plate. I personally believe the plate is assembled out of lesser spren related to the respective radiant. I think the windspren that gathered around Kaladin were because he was so close to saying the 4th Ideal, and they were ready to be summoned as Plate
Then, there's the part where Renarin is going up to the Oathgate where the Voidbringers fly down to him and appear to salute him. I think that has to do with his spren being corrupted. They seem to see him as one of them, which may come up again.
Anyway, those are a couple I completely missed, my first read through.
