I loved these too. After I finished reading them, somebody pointed me at Ursula's Paladin Rant, which is apparently where she laid out the thought process that became Caliban. I find it facinating.
https://mobile.twitter.com/i/moments/918567234896789504?lang=en

(Although I still have problems with giving him the *name* Caliban, because c'mon, Caliban is the creepy dude on the island in The Tempest!)