I haven't read any of this besides the OP, so my post is in response to only that. 

This 'pre-made/pre-determined role' thing is bullshit. I've seen it most often in casual or free RPs where the creator requires folks to play accomplices to their oh-so-special GM character. I don't see the appeal of throwing away my own creativity or player agency to be forcefed a role to prop up someone else. 

Any character in one of these pre-made roles is better served by an NPC. Even then, these ought to be narrative stories and not roleplays, because chances are the creator has a very specific plan for these characters to follow. Just write your damn story on your own instead of trying to make people play your characters.