As far as networking, from what I could see the only real change casaos was doing was mapping its dashboard to port 80, but not much more. Is there anything more I should be aware in general?
It depends on how you have things set up. If you’re just doing normal docker compose networking with port forwards then there shouldn’t be much to change, but if you’re doing anything more advanced like macvlan then you might have to set up taps on the host to be able to communicate with the container (not sure if CasaOS handles that automatically).
I would separate the media and the Jellyfin image into different pools. Media would be a normal ZFS pool full of media files that gets mounted into any VM that needs it, like Jellyfin, sonarr, radarr, qbittorrent, etc. (preferably read-only mounted in Jellyfin if you’re going to expose Jellyfin to the internet).