Actions such as Team damage, team attack frequency, vote and getting voted on will be recorded and influence a symbol that shows whether a player is nice or not. A longer lasting effect as a consequence for trolls.
#Player reputations
pearl kindle
toxic pebble
Would be a witch hunt though. I have alternative feature. A reputation system hidden from everyone else but you.
If it gets too low you get put with the other trolls in separate servers from the mainstream gamers.