I can totally understand the fear of cleaning house, that can really hurt a chapter for years. But I also agree that you can't possibly recruit a solid membership with a bunch of lazy asses who bring everyone done and influence others to be lazy too. It's you vs. them in a battle of coolness and you can't win that way because people are naturally apathetic when they think that someone else will take care of it.
I know that you might have tried this already, but have you really analyzed your assets to the chapter? Who do you know? Who are you connected to? What kind of events, besides the usual blow-out parties, can possibly interest your members? I know that this sounds kind of child psychology-oriented, but is there any way to get them involved without realizing that they're actually benefitting the chapter? Like a brother who's an art major who just wants to sit around and watch anime during spirit events could probably help you design some kick-ass banners or even fliers for your parties. Or you could host a party or barbecue at an off-site location or alum's house to benefit your national or local philanthropy? You could also seek a sorority to co-host the party - trust me, if you ask nicely and bring cookies, sororities like to help :-) The key is finding one that isn't all about the rep. and won't see it as a 'social misstep' if they host one little event with you.
I'm glad that you have an active exec board this year, leadership is really important for solid changes, obviously. You will make an AWESOME officer!
