Finished reading through "Aliens and Alien Societies" though ... it has become a zero-sum game, as I put two more SF writer worldbuilding books on reserve. Would have reserved more, but the other resources I was looking for were not in my library. Really, it's about time some insane, ridiculous book I was looking for wasn't. ;-)
I have taken some notes; I have a clearer idea how I want the Derithe to work. To the point where, if this were somehow to get published and I were going to write a sequel, I'd want to crack the mystery of my little alien deus ex machinae ... (machinas?) I also got a good grasp that building earthlike planets for my people to inhabit is actually going to be easier than I thought.
Gee, that's a nice feeling.