TrueNAS is pretty cool, and it uses ZFS by default. Should work for your use case. I couldn't get into it, though. I have to manage every detail, absolutely no exceptions.
It looks like it's for their immediate family. I had issues with this when I was supporting people I didn't live with, but if they're using the same PC, it shouldn't be an issue until something breaks.
I've heard good things about copyq, but I sometimes run into compatibility issues with it for some reason. Clipx is also good, straightforward and easy to understand
I'm tired of hearing the advertisers' opinion. It wouldn't be so bad if it were remotely accurate.