Troubleshooting notes
This isn't an issue so feel free to close this out. Just wanted to submit some troubleshooting notes that may help others:
Cloudflare
It is possible to use cloudflare with letsencrypt, however to get up and running quickly: disable routing through the cloudflare service (click each DNS record's orange cloud to turn it grey).
Server Requirements
I attempted this with a 512MB ram Digital Ocean droplet, but mariadb would hit a memory limit and its container would be constantly restarting, resulting in no access for a short time. Found it works perfectly fine with 1GB ram.
Collabora
Still working on this... getting this error: https://github.com/owncloud/richdocuments/issues/153
Spreed.me
Still working on this...
Getting this error message when going to the spreed.me app: File not found. The specified document has not been found on the server.
Misc (not related to repo, just nextcloud)
For notes and news synced to iOS: https://itunes.apple.com/de/app-bundle/cloudnotes-cloudnews-owncloud/id917640118?mt=8 And enable the qOwnNotes app in nextcloud, and download for desktop: http://www.qownnotes.org/
qOwnNotes desktop will import your .enex file from evernote and convert it to markdown(!). WIth the above, it's a complete replacement for evernote across your devices.
encrypt notes with keybase: https://github.com/pbek/QOwnNotes/blob/develop/doc/scripting/encryption-keybase.qml