Id make it a vote in the MA for a month before making the decision to just cancel cross country chat. It could have a bigger impact than anyone expects.
I don't agree with banning communications, and don't think cutting 200 or PMs would make any difference. It might make it less fun as you cannot talk to the community anymore.
For all it's worth, if you can't take crap talking from another player, perhaps you should find a nice off-line game to play. Basically any online war game is going to have these types of people.
The .report button should relay a message to the Hitech and if it's bad enough should result in a week radio ban, and if continues, a month ban, and if that continues, than a 6 month radio ban.
The key should be to punish the individual for their actions. Not punish the entire community for the actions of a few.