At present, I'm playing around with a very small fileserver based around an Intel NUC, with the boot environment on a USB flash drive ("usbflash") and then using a large spinning disk ("HDD") for bulk storage. The HDD is entirely managed by ZFS, where the usbflash is a standard *buntu install with ext4 and a single large partition.
Is it possible/reasonable/smart to move /home, /var, and /tmp over to the ZFS partition? The write speed of the USB device is quite low and I'm also trying to minimize the writes to extend the usbflash lifespan. But at some level I'm also just messing around and trying to learn what does and doesn't work with ZFS ;-)