rerush after dropping?

Not really; you will have less of a chance next year than this year. Other sororities will think twice before offering a bid to someone who couldn't afford it the first time. It is really hard to overcome being a financial risk. Your current house would most likely not give you a second chance. Also depending on why houses may have dropped you during recruitment, they are likely to drop you again next time. If you are close to dropping you should talk with your chapter leadership to discuss. If you initiate and need a break due to finances, they may be able to help you work something out. Then again they might say that's it, no second chance. They'll have to tell you the options. But honestly it sounds like you aren't exactly committed to your sisterhood and are looking for an excuse to trade up to a 'better' house.

commenting on the post above, I am in greek life, and I know many girls who stuck with their sorority and dropped before initiation because it wasn't the right fit for them, and rushed as a sophomore and love their house now. It is easier to rush as a sophomore, and sororities do not have access or knowledge of wether you can afford it or not, so that isn't a factor. Houses that have dropped you the first time may ask you back when rushing as a sophomore, they have to meet a certain quota for sophomores, so sophomores usually get preferance. and you might feel more comfortable rushing for a second time, being that you know what is coming. Rush is hard, and it is difficult to find the house that fits for you especially when you're in a new environment. You can take a year off and get a better feel for things and rush again. From personal experience and knowing many girls who rushed and dropped and rushed again, it is very obvious that you may have a better chance as a sophomore, you may also make friends who are in greek life and get a feel for what sorority may fit you best based on the personality of each house.