The actions Mozilla proposes sound awful. I believe that a secure (from the NSA) Internet is the way forward. But this seems so goofy to me. There are legitimate reasons for a site not to be hosted on HTTPS.
* It is a static site with no forms or logins
* It is non-critical info
* The site operator can't afford a certificate (Let's Encrypt is only one site...)
As you say: Color-code sites with a bit more granularity. Don't cripple the cleartext web.