Maybe you would like to try m4b-tool chapter-adjustment by musicbrainz id or silence-detection? :-)
Disclaimer: I'm the author - https://github.com/sandreas/m4b-tool
I once planned a chapter database (https://www.chapter-db.org) to collect work like yours, provide an online chapter editor and bind an api to m4b-tool, but i did not have the time to finish the project.
I once planned a chapter database (https://www.chapter-db.org) to collect work like yours, provide an online chapter editor and bind an api to m4b-tool, but i did not have the time to finish the project.