I'd love to have some kind of "XXX edited your chapter YYY" notification. I prefer to know when author\owner\editor edits my chapters. Similar notifications for liked or bookmarked chapters would be nice, too
I've thought about this one to. However, I think it would be complicated due to the disparity of edits. Yeah, if an author does a major rewrite of a chapter, addressing plot-holes and doing some serious improvements, you would like to be notified and re-read it, but if it something as minor as some light proofreading or adding a comma to a sentence... then, not so much. I would also be easily exploitable as authors could use it to spam the same chapters over and over.
This is why the "edit silently" option exists, for minor changes you don't necessarily want on the record. I guess that would turn off these hypothetical notifications, as well. The exploitability is a bit minor - you can already spam messages, for example, or repeatedly like/unlike if you want to flood someone's notifications (I hope I'm not giving anyone ideas). Harassment is harassment, and you can always contact a moderator if someone's giving you trouble.