Just finished playing through the Story so Far to refresh, and there are a few things I noticed at the tail end of the marathon.
I just noticed that all of the Foreteller's keyblades have the masters eye on their keychain. They never focus on it, but you can clearly see it when they show all of them at the beginning. This could be a way for Luxu to watch them without ever stepping back into the town.
I know there's more I noticed, but after 9 weaving stories, I'm sure I forgot some. Can't wait for KH3. Only a few more days.