Help deciding how to properly use NAS

[TheDreadPirate]

In the case of a motherboard failure, if you used a ZFS RAID array and moved the drives to a new system you can easily import the existing ZFS RAID. Much less problematic and much simpler than classic RAID5's.

This is what a lot of people do, including me. I store my media on a RAIDZ-1 ZFS array. The ZFS functional equivalent to a classic RAID5. You can also go do a RAIDZ-2, equivalent to a RAID6.

A Synology NAS doesn't do anything special. They just slap a UI on top of, usually, ZFS. And they don't do anything with ZFS that you can't do on plain Linux. Same with TrueNAS. At least with a custom built system you can replace JUST the failed part. A failed Synology NAS would require replacing the entire unit.