It seems like a fair bit of effort, and will probably need to be done repeatedly (you won't get every griefer in a single instance). And in the end, you are theoretically playing a game of like minded individuals who don't grief, aka, Mobius. Kudo's to the OP for thinking through the process, but I don't think you'll ever catch every griefer to block, and it's much easier to play solo or PG (Mobius) to achieve the same result. As far as the "everyone should play in one mode to even out the BGS field", I'm not sure I buy into that argument. Between different time zones and instancing, people play their own game, not much you can do to change their influence regardless.