> Except for maybe another pool. Which is going to hurt since ZFS with buying everything up front is VASTLY more expensive than RAID where you can grow the arra

> Except for maybe another pool. Which is going to hurt since ZFS with buying everything up front is VASTLY more expensive than RAID where you can grow the array as needed - under the assumption that the storage needs grow slowly, which they typically do for home users. your backup pool doesn't have to match your working pool. it certainly doesn't have to be the same size. it just has to be larger than the data you've got. so you can build a big 64TB pool, and back it up to a set of external USB drives which expand as your actual data expands. similarly you can turn on a bit more compression for the backup pool than you might want on the main one.