my very best friend is a fantastic Alpha Gam at a school that does second semester rush. This is what they do:
Rho Chis go nuetral first semester. I know this is a long time to be dissaffiliated, but it's the best way to keep things fair.
they also do their recruitment over a holiday weekend (president's day? MLK day?, I'm not sure) that way girls have three "weekend nights" and only have to give up one week day.
I think the best thing you can do to get rid of stereotypes is to get out there and meet as many girls as you can. One great benefit of second semester rush is that you get to have alot more "casual contact" with the pnms. you can help with move in, eat lunch with freshman etc. I know there are some limitations to this (going in their rooms etc, etc), but you can do alot to get to know pnms before rush.