Although I'm posting on-topic here, it kind of feels like I'm going OT, based on the rampant paladin discussion.
Sometimes it's not about coming up with different archetypes so much as coming up with a culture that justifies what they are.
[snip]
I forget what I did with goblins and kobolds, because I can't find my notes.
This sounds very similar to a "real-world re-flavoring" of D&D races that I did for my Greek setting. I wound up making the kobolds the "Pelasgians" (the people indigenous to Greece before humans moved in) who worshiped big, baby-eating dragons. They most often serve as slaves to the bigger races, except where they've managed to establish a home in a place where the humans won't settle.
The goblins and bugbears I made into the "sea-people" who raided the coasts and harassed nations like Egypt.