I found k3s to be VERY noisy in logs - I definitely recommend log2ram if you want your SD card to last very long! (Or use different external storage). I had two Pi nodes with corrupted filesystems until I made the switch.
Awesome protip, thanks! I normally keep a rolling log history backed up to S3 but I'm thinking for these Pi nodes there's probably going to be literally nothing of consequence running on them, so this looks like an ideal solution!