I think the top/top percentage (10-15%?) of players on a server should get at least + if not a neutral 0 (how much based on average rating, ppms etc - or some clever way :p). Someone could be top on e.g sKy-e and be say 1.5x ppm of average compared to the same person going on FA1 and getting 2-3x average ppm and they'd get more rate on FA and may even lose rate on sKy-e. It seems if I get a little over 2x average PPM I will always get a +, REGARDLESS of anything else. Someone shouldn't lose rating being top killer/xp gain on say NBS because they only got 1.4x average ppm...
its a public secret that FA#2 is the best rating server