You actually have to rank the houses so early on??? At my school you saw who invited you back, and then chose which houses to keep... the only time you "ranked" houses was after pref.
I'd be curious to see how you ranked the houses - if only because my school had a lot fewer sororities (only 5) and 4 of the 5 that were at my school are also at yours.
Good luck with the rest of rush!
