Would you mind to try Nginx caching in Plesk Onyx 17.8 Preview?
This would be very helpful to get your experienced feedback here http://www.surveygizmo.com/s3/4165754/Plesk-17-8-PreviewPasquale commented
It asks to be able to foresee the installation of varnish and its update from the Plesk panel
Thank you for your input. We will consider the possibility of implementing this feature in upcoming releases.
Since Plesk Onyx panel admin will be able to install different MySQL versions as a Docker containers, then the DB servers can be connected as remote DB to Plesk.
In the tools, as in the case of php, insert the instrument for updating the version of data base (for example, switch from mariaDB 10.1 to mariaDB 10.2)