I'm working on https://github.com/uberswe/beubo - It's a CMS similar to Wordpress but written in Go. It's still very early and it has a lot of bugs but what will make it powerful is plugins and themes. Performance is the biggest difference between Wordpress, plugins will most likely use RPC/gRPC which means they could be written in any language.
I'm mostly writing it for use with my own projects like https://tournify.io but it would be awesome if a few others found it useful too. It's a nice way for me to practice my Go programming skills.
Interesting project. I'm creating my own blogging CMS with a similar tech stack, Go + sqlite3 + Go templates. Works well so far. I plan adding plugins as well. Do you use a special library to support those?
Right now I'm leaning towards using https://github.com/hashicorp/go-plugin
You should link your project, it would be interesting to follow.