I would love to use xfs on my NAS setup but no checksums is a deal breaker. Checksums have saved me multiple times where I've been able to either repair files with parity or restore from backups.

Without checksums I would have overwritten my backup data and lost a ton of files because the drives were reported that everything was OK for months while writing corrupt files.

Thin provisioning with lvm is afaik problematic, because the file systems aren't aware of it and if you run out of space you're screwed