I already have it down to 6, smooth rendering off, clouds off, snooper disabled, and there was one more video setting I changed but can't remember ATM what it was, but all to reduce lag. I can turn it further, of course, but this doesn't seem to be the same lag as I get when loading chunks (In unmodded minecraft I can play on a 12 chunk setting no problem; with most modpacks on the launcher I go down to ~8); I'm only getting about 2 FPS when standing perfectly still for several hours on this mod; also on the main menu, where lag is unexpected.
I've considered it. Uh... heheh... I suspected that one of those might have been the reason it was so slow, actually. I could try adding one or the other, but I'm pretty sure both of those are to optimize chunk loading and I don't think it's the problem.
Sorry, I'm well aware that this pack's pretty amazing, and would love to play, but I think one or two mods are interacting badly.