Personally I think increasing the spawn rates makes sense, where there's a community of chinese goldfarmers that legit make a lot of money by just having a team of 5 or 6 people farm all of the various spawn points.... things have gone too far lol. I've seen horde and alliance working together literally so that one person can get the herb which just goes to show there is a wacky level of detail that could potentially be game breaking.
Personally I think making the respawn time more unpredictable, and in a range of 30 to 45 minutes would be a great start, as well as more closely monitoring who is farming the black lotus, just to verify they aren't doing any exploits.