Group owners need more tools to be able to manage chat / group users, especially when there are people that create a new account every day to post horrible things to groups.
Some options that would help:
-- pre ban capacity ( use wildcards on name to prevent users who use some variation of the same name every time from even joining, or to limit their ability to post to the group)
-- have a setting to allow group owners to stipulate that an avatar needs to be at least X days old before being able to post in chat
-- limit the ability to post links (if you post one, you're automatically banned) with domain exceptions (i.e. allow primfeed, gyazo, etc)
This would help with scammers, trolls, and allow group managers / owners to give their groups a more positive experience, maintaining the ability to have group chat, without enabling or at least limiting the ability of creeps and scammers to disrupt.