- a) impose less on the imagined world and other players, and
- b) are more interesting, compelling, or challenging for players
By imposes on the world I mean you want something for your player that will make certain things have to be true for our imagined but unexplored world. I had a player that wanted to play a Drow exiled because he was good. So, if I let him do that, first, it means there are Drow in my world, second, they are not innately evil, or at least their evil can mutate like hair color or something. It would also mean his character would have special racial powers, infravison, languages etc. It seems that impositions on the world fall into these two main categories assumptions about the greater world and personal power increases. Well, maybe a third as well-- player desire for the spotlight.
I don't have a lot of experience trying to inhabit different creative and interesting characters in rpgs. I usually just play me with magic. Though I have played an alcoholic mage, a naive robot, etc. Still, I'm no expert on what someone who detests OD&D style "faceless pawns" wants in a character background. Is it hooks that can help them decide what this imagined person would decide in different situations? "He was an orphan so he's doesn't want to leave the kids behind." Or, is it more about a challenge? "Hold on, my priest's 23 strictures make this one tough."
I'm running out of time and have to get to work, but what would be some background details that might be true for both a) and b)?
- Things common to all humans or societies seem like they would work: having a parent die young, being a member of a big family, moving a lot as a child, being an only child, etc.
- Pseudo-medieval jobs might be safe (but even this depends on the weirdness of the world) : farmer, blacksmith, ostler.
- Privileged backgrounds seem more in danger of assumptions: if you're a member of royalty how does that work in this world? How much money do you have? If a lot, why are you risking your life in the caves? Maybe you like adventure but your party members could probably make money safer by just holding you ransom.
- Personality or physical traits seem like a good bet. I think my hireling traits chart does a good job of hitting the biggest ones. You're really tall, or never drink, foolhardy or sullen.
- Crimes seem like a pretty universal thing too: did you murder someone in a fit of rage, commit adultery, are you a secret arsonist?