The thing that I’m most looking forward to: the ability to have multiple drives of different sizes, and expand the array with new oddly-sized drives (great for

The thing that I’m most looking forward to: the ability to have multiple drives of different sizes, and expand the array with new oddly-sized drives (great for a homelab NAS built of spare parts; btrfs can do this, but zfs can't), combined with being able to set some drives as caches (eg having the filesystem automatically store frequently-read data on an SSD and rarely-read data on HDD; zfs can do this, btrfs can't)