Hey! We also make composable events for Alexandria, where our editor can generalize from just chapters -> books, to notes -> books -> magazine periodicals and so on. Our main event structure uses (index/collection) 30040 that holds together the section/chapter events, but also display composed 30023 events like you have. We chose to work with AsciiDoc over Markdown because there's only one standard, but the wiki and longform events are fine with Markdown.
The specification for the structure we're working with is in our documentation, titled NKBIP (Nostr Knowledge Base), and are working on other features like nostr citations and nostr based file systems. You can check them all here, as a collection. No shortage of testing data! We have essays, books to the full Bible (~40k linked events)
We also have a tutorial on how to publish with our client.