I'm just trying to ensure that I get the best possible setup
I think there is no such thing
make sure that I still understand how it works and how to implement it correctly and be able to maintain it
KISS: use ext4 and rsnapshot
Snapraid (I don't use it, but many others on the forum) seems to work well, but I think you need to spend some time to understand how to set it up and how to fix issues, if they come up.
In any case you should have some kind of off-site backup like cloud or external drive you store in a different place.
Also check the user guide which is linked in my signature.