Just my personal answer, but I always took the animist/ranger vs cleric/champion(paladin) to be a cultural development one. . .Cleric/paladin always seemed to imply a more heirarchial, later development religion.
This could just be a bias based on earth history, with animists being closer to pre-judeochristian religion archetypes, and clerics more like the JC archetypes.
Using an RM2 answer, I'd probably call:
Shaman
Animist
Priest
to be a progression from the earliest, least developed type, to the later and most developed type.
By development, I mean dogma, heirarchies and rules. . .
Rangers, like animists, seem less tied to a dogmatic, structured religion archetype.