Do you use the official LibreELEC build for ODroid, or is one of your device trees geared towards the C2 as well (I only ask because I didn't see anything specific in the device tree)?
My builds do not work on Odroid C2 because it needs a bit different kernel config and a special u-boot. Raybuntu's builds (32-bit userspace: thread-4248.html) and official LE builds work really well.
Do you have any opinion on whether any of the differences in the hardware are better/worse? For example do you suggest the 1GB vs 2GB boxes or the 8GB vs 16GB eMMC's or 100 Mbps versus Gigabit chipsets?
I think for LE 1GB RAM is enough but it's good to have Gigabit Ethernet. If you get a decent SD card it doesn't matter what's the internal memory size, you are only limited by card size.