In what order should the stories of my collection be? Can BookyAI help?

Yes, from version 1.9.20. On the book's page, press "Reorder" above the chapter list. In a collection a bar at the top offers "Arrange for the reader". BookyAI reads what each story is about and proposes a reading order: a first story that hooks a new reader at once, variety of mood and length in the middle so two similar stories never sit side by side, and the most memorable story last. The proposed order appears in the list, with the reason under each story it moved and one line on the shape of the whole. Nothing changes until you press "Apply new order"; you can move stories by hand first, press "Propose again", or cancel.