I think we need to keep the release notes, they help people understand why they would want to upgrade. Let's make them succinct, however. I like the list of major parts, maybe we can add "Boards" to "Architecture Support" and add another part for other subsystems like, crypto, graphics, net, file systems, etc.
That is basically how it was done before. Look at the top-level file nuttx/ReleaseNotes. That is ALL previous release nots. It is divided into two major sections: New Features and Bugfixes. Within each section, these are enumerated broken out by just the kinds of categories that you describe.
The organization of the release notes is fine, it is just making the level of effort needed to produce them manageable. This begs for some kind of tooling.
