This almost-newbie is trying a reinstall (Docker container)

Hi,

After several members here helped me with my newbie questions, I was able to get a Nextcloud instance running on my Plesk-administrated server (Ubuntu 16.04 with Apache 2.4.29 and PHP 7.2.14). Now I have updated to Ubuntu 18.04, and before I get too much content uploaded to my Nextcloud server I want to try a going with a fresh installation.

Specifically, I want to place the data directory outside the web root, per the Admin Guide recommendation. My first installation had the following directory structure:

/var/www/html/mynextcloud
/var/www/html/mynextcloud/data
/var/www/html/mynextcloud/config
/var/www/html/mynextcloud/apps
/var/www/html/mynextcloud/custom_apps

What should I change for my new installation? All other environment/config tweaking advice is also welcome.

Thanks for any insight.