If you do decide to look in to containers again and get stuck please make a post. We are glad to help out. A tip I can give you when asking for help. Tell the system you are using and how. Docker with compose files or portainer or something else etc. If using compose also add the yaml file you are using.
Euh depending what you get. Don't be fooled by their "ZFS" offering. It is a very very outdated and forked form of ZFS. I converted to TrueNAS scale with my qnap recently. Worked great. Although some things you have to do a rather advanced for more casual users.
Not with ZFS and their for TrueNAS. A hardware raid card is not suitable at all. Even if you set it to jbod mode. It shut actually be flashed to IT mode if that is possible with that card.
If you do decide to look in to containers again and get stuck please make a post. We are glad to help out. A tip I can give you when asking for help. Tell the system you are using and how. Docker with compose files or portainer or something else etc. If using compose also add the yaml file you are using.