SF New Year's Options and Advice Needed please - visiting

Looking at a couple parties on New Year's in a few weeks when I visit SF - need some advice from you guys as to type of crowd, best place for a couple single guys to hit and have fun with good single female/male ratios, opposed to mostly couples.

W Hotel Party?
City Hall Party?
Westin/Hyatt/Hilton?

Most all of these seem to be like $80-100, which is fine for New Year's but want to make sure we're somewhere fun with a good attractive crowd - open to scenes but knowing that some places get really segregated hoping for mostly brunettes/blondes opposed to ethnic.

Thoughts?

Thanks guys