ideally my home directory on laptop and desktop should be identical, or better yet, my laptop homedir should be a subset of my desktop homedir.
I really like the way OneDrive has done it where you can mark files as "keep on this device" so you have offline access later, and everything else is automatically relinquished to save disk space. It's smart, if opaque and clunky to work with.
Similarly, the packages I run on my laptop and desktop differ only slightly. the desktop environment and certain associated programs aren't the same, but everything else is the same and I want it to be configured the same.
So far I've approximated that with syncthing, so that my changes to certain config files and documents on the laptop get synced when I get home and vice-versa but it's a kludge. I wonder if zfs can do something like what I want?