I would say keep it, but stay away from Wordpress (unless you want to use the blog as a live demonstration of the dangers of automated vulnerability scanners). I'd say a static site (published on Github Pages) would be a great idea, as it's quite easy to set up, requires no maintenance/updates, and it's easy for everyone to contribute and improve other's posts.
About the lack of HTTPS on Github pages, we could keep the site's contents on GitHub but host using our own server which would allow us to use HTTPS. I can provide one free of charge if necessary.