If your FC prides itself in being a safe place for it's members, there should be something like mute that can assist management to maintain that. If as a member, you can't trust or respect your leaders to use it properly, you should consider finding another FC.
Kicking a member from the FC is a poor only option. I think mute would be useful in some situations for example if the offending member/s are bound by duty and you can't pm them, or if things are escalating quickly.