CRZ just exacerbates an existing problem: The game isn't fun when you get ganked by someone with such an extreme level advantage, such that you have no hope (even 10 vs 1 in some cases) of coming close to damaging the ganker. I believe the sensible solution, is to not allow opposing factions to see anyone more than 20 levels below their own level. Or maybe 10 levels below. Obviously this won't help an 80 getting ganked by a 90, but it certainly can't hurt.