I'm curious; do you explain somewhere (my brief web-searching failed) how you define or determine the difficulty of building the various polyhexes? I can imagine there being various plausible formal definitions of "difficulty" which would give different orderings. (Or was it done by subjective judgment / empircal testing?)
I don't have any place where I've discussed it in detail, but we had a brief discussion about it here today (during which Luis pointed out there's another error I hadn't spotted...sheesh. It's not an easy game to design)
At some point i'm going to write a document detailing the construction. but not for a while
it has to do with "degrees of freedom in building" different polyhexes.