I can also tell you that Fox are pretty on the ball when it comes to the fans,This magical universe where Bernie Sanders was elected and got Universal basic income and Unified healthcare exists sounds dreamy. I suppose Elon Musk invented unicorns there too.
I like how you left the rest out just so you could stay bitter.
I saw definite signs of skullage on the first alien corpse encountered aboard the LV-44-40 station. However, the other aliens in Defiance appeared to be entirely skull-free even though one or two of them appeared to have the smooth carapace of the original. Were they supposed to be young adults while the so-called "ridge tops" were their fully-matured siblings?
That wasn't intended, but I know what you saw, because I see it too. It's the unintended side-effect of the shape of the front of that head being shattered.
As for castes, I'm not really one for how those particular ones evolved. There's a definite continuity to how those ones worked, and the praetorian in #2 played into that, but I've got a very distinctly clear idea of how the biology works and it wasn't something I could put to full use in Defiance. Not to say I don't love what I drew in there, but if you gave me a series to myself, I'll give you a clear vision of how I see the biology working in regards to the caste system.
At the end of the day, changes were made to the look of the Xenos in Defiance. I started off using the ridgetops as mindless drones in need of a hive mind creature (queen, praetorian), and that brain bug was the Big Chap, but I had to change it, and with that I started to tweak things into a design I could use over and over again that was a compromise between the two. I kind of ended up taking the Big Chap's dome off and smoothed out the skull. to be more in line with the dome on the runner/big chap. It's a mix of all three.
It's very faintly visible in some shots in the shuttle at the end on BluRay. If you're looking for it and don't blink.
I must be blinking every... time...!