Like the one thing I wish every MMO would do, is allow the PvP mechanism to kill bots. I don't care how much like griefing it looks like, but if you provide a "Engage PvP (Suspect bot)" mechanism, so that killing the bot forces it to respawn in a "jail" somewhere it can't teleport from, can't shout/yell/say from, makes it vastly easier for GM's to count the bot activity. Because a real player will actually respond to a PvP fight by fighting back or running away,
while a bot will just stand there and die, because even if it has PvP countermeasures, I've never seen a bot win against a real human except by being overleveled or ganged up on by PvP combatants.