Also just a thought, but if limiting the hashrate spreads among new coins, a captcha should be required to create a mining account on the hashrate-limiting pools, otherwise large farms will just automatize the creations of lots of accounts xD
But it does make controlling the farms in China/Russia/India a little easier to control. If you limit at the few selected pools, those pools can now be protected at the network level. Newer networking kit has GeoIP location enabled Access Control Lists. You can simple *block* China.

Nothing is foolproof, just like computer security. But if you make so many layers of shit for them, they will just move on to softer targets.