Would be nice to have a feature in Virtualmin which allows a client to create a staging/dev site of their website. Almost similar to cloning but will allow the website owner to commit back to their production website any changes done in staging/dev site. Similar to this one https://wpengine.com/one-click-staging/
I would like to also suggest to highlight or make bold the warning which appears before cloning a site. Or have the option to copy the database.
"Warning - any web applications in the cloned virtual server will continue to use databases in the original virtual server until their configuration is manually changed."