high school

I mean as long as you continue to have a good attitude in each of the rounds and treat every sister you talk to with respect, it should be worth rushing again. A lot of girls rush/re-rush sophomore year and end up pledging. Just be open minded again and remember to treat every house nicely, that way you can maximize your options. A higher gpa can't hurt, but honestly even the "bottom" chapters wouldn't have dropped you for grades without a good reason. If you're concerned about your reputation, maybe clean up a bit and join some clubs to improve your credibility. Most groups don't check social media because realistically there's not enough time to check each pnm's stuff. If a sister from a chapter knows you have a "bad" reputation, yeah, she might blacklist you, but I doubt you know someone in every single chapter. Unless you're going to be a jerk during rounds it shouldn't be a problem next year.

Best of luck to you! You seem to have a good attitude about this and I wish you well for rush next time. Informal might be up your alley too, so you could always contact panhel about that if you're interested. Some chapters will need to extend bids in the fall based on how many seniors they lose this may, so just something else you could try, with the exception of the 4 chapters you know girls in. Cheers :)