gphi2k-
Isn't the incentive to have your sisterhood continue to grow and thrive? Just my take. I know that we had to change our thinking when I was in college because we had very low turnout at recruitment. We had to look at recruitment as a 365 day process, and not just a week each semester. We invited girls who might be interested to all kinds of events from service projects to mixers. We ended up getting a new member class of 13 the next semester instead of 6, which was quota.
Just a thought
Email me if you need any advice on PR though!