Definitely needed for all message boards. Some hold that you really shouldn't have mods, I've heard that on other sites. Well I think that's silly. You really do.
Guess it all depends on the post. To what extreme is it all just no good.
Good to give warning but to have it done by private message which I'm guessing that's the way you'd want to do it. And I wouldn't allow one to argue with me or challenge me on the open board. I'd allow a measure of that through PM's as I was a mod once and that's what we'd do.
We were always open to at least consider their opinion and hear them out. You probably already know who is basically fair and reasonable and who just never will be respectful. I'd say be at peace within yourselves for nearly all the time you really do know that you know what should be done.
I'd make it twice and then three days....then a week.....then a month. Might seem heavy handed but I found people considered the 3 day thing something they would always be willing to endure.....small price to pay.....but hey... a week? That's substantial time away if one likes to talk on message boards.
It would depend on the degree of their hostility. Generally speaking I'd stay with a 3 day, 7 day, 1 month plan. Of course if they're gone for a month they may not be back but if they come back they're going to know extreme misbehavior will take them out for a great degree of time.
The peace of mind for the mods should be a priority. Good members will respect that. No Christian should have to be subjected the poisonous spirit, strife or contention that an extreme discontent want's to inject into another's life. If members can't generally be nice and kind they shouldn't be here.
I think there should be a consensus among the members and an agreement that if a mod takes a certain action you can make a respectful appeal but be willing to accept you may win some and loose some.....and be willing to have it so. Members should assess to what level of being upset they choose to be about something not going their way.
I recall as a mod thinking by gosh they're going to take my actions to the United Nations for resisting what they think they should have without limit....free speech. Well a peaceful site won't allow ALL SPEECH, mean speech or destructive speech. All should be striving to make this a place of love. All should be committed here to be one who endeavors to keep the unity of the Spirit in the bond of peace. God Bless!