Long time no hear ... I'm really happy that I was able to dedicate some time for a topic that was one of the very first when joining the community.
Why? There has been some nice ruler rework recently, and so I got a
friendly ping about what had happened to the so called "Comments Ruler
Control" I've proposed years ago when working on the Writer notes (OOo Notes2).
Consequently, I've started the Design Whiteboard "Comments Ruler Control" that contains a rather complete specification for that feature. The basic idea is to provide a new user interface element (next to the ruler) that enables the user to toggle the visbility of the Writer comments. Here is an exemplarily mockup for the case "Ruler Control Expanded" ...
If you want to know more - have a look at the Whiteboard. And if any developer wants to jump in ... that would be really awesome!