Couldn't agree more. I feel the changelog is very important and invest considerable time each release making sure that ours are clear, concise, and readable and link to documentation and more info when warranted. In fact, I spent 5 hours last Monday going through all our pull requests and issues for the WP Migrate DB 0.7 / Pro 1.5 release and distilling it down into our changelogs. It's very manual and tedious, but I think it's worth it.