I don’t have an answer to everything as I was travelling last week, but I now know that smart_mute is unused and will be removed so you can leave that out.
We’re in the process of some documentation changes and cleanup, so I’ll take into account the change to the show_all_inline_media that you’ve noted. These changes may take a number of weeks to ripple through to be visible as we’re working on the backend that hosts the docs.
I’ll try to find out about those other settings here though, and get things clarified.