Currently the zfs filesystem's "setuid" property is limited to files - it has no effect on directories within a zfs dataset. (crossref: man page error, bug #227406)
setuid on directories is extremely useful in many scenarios, and for UFS at least is the standard way on FreeBSD to mandate+enforce ownership (including ownership inheritance on new objects) within a file system or directory path.
Lacking zfs setuid support on directories, there is no way to achieve this AFAIK for file systems/directory paths on zfs.
Can the setuid property be enhanced for zfs, so that it does permit ownership/inheritance control on directories as well?