This book wrapping up all of the open ends in the story feels both very pleasant to read but also pretty sad on a deeper level. I really don't want the main story to end but there needs to be a last chapter eventually or it'll lose its greatness.
Rozemyne's future plans for Alexandria must have been quite a shock to those nobles, bet they didn't think the Saint of Yurgenschmidt is a Gremlin. Which brings me to wonder how fast books will spread now that she does not have borrowed authority but actual direct authority over the entire duchy. I'm afraid Ferdinand et al will have plenty of work making her reconsider book plans that would put the duchy's vital industries (like farming) at risk.
I won't be surprised if they actually manage to find a use for them again. If only as some form of decoy to make an enemy reveal their position