What is this, a creative idea? I'm surprised, haven't seen one in a long time.
I must say I actually like the idea, apart from the loot, which would be op.
What could be cool:
when you are in a fief, you can initiate a fight vs anyone else. The attacker can set a certain gold value (from 10 to 1000) that both of you will bring to the fight. Everyone who is in the fief right now can join the fight on either side, everyone has to bring the same gold amount. No one can see who applied for what side
. After the fight, the loser(s) have to hand the gold over to the winner(s), and the losers will be kicked out of the fief for 24h.
Fight will take place in a tavern, and fists only, maybe a few beerkegs lying around to throw
Of course, it's very low on the todo, so don't count on it anytime soon. However, it just made it on the nice-to-have list.