As for comments, I think JSON is only "human readable" by accident. It was never really meant to be read by humans, and was created in a way that implicitly discouraged people from trying to write or edit it by hand. Many parsers are picky about whitespace to discourage people from trying to create config files in JSON.
"comment-subject-author":"this is a comment, we dont need out of band communication, thats a bug, not a feature"
Ah, so now you're encoding out-of-band communication into your data? How is that not worse? This also completely breaks if your data is validated against a schema, or if your comment gets parsed as a data entry. For example, in Javascript projects you define your dependencies in package.json. I can't add a comment to explain why I had to add a strange dependency, because npm will interpret it as a dependency itself and then break.