I really value simplicity, security and reliability and therefore use an offline generator for static HTML pages. I don't really see the use case for something

I really value simplicity, security and reliability and therefore use an offline generator for static HTML pages. I don't really see the use case for something in between a "fire and forget" static HTML site and a well administrated full featured Wordpress (or similar) CMS. As soon as you add PHP or other server side executable you'll need to update constantly and run into update problems.