On the importance of numbers... If the difference in size between the smallest and largest chapters isn't glaring (like, the smallest chapter has 80 and the largest has 100) then it doesn't really matter. But if it is glaring, particularly if there's one very small chapter and the rest are quite a bit larger, it can and does hurt the small chapter.
My chapter is, and always has been, in exactly that situation. We returned for rush one year with only 10 women, when the other 4 sororities returned with 70 or more each. Plus, as a new chapter, we didn't have a support base of chapter alums to draw on to help with rush. PNM's often cut us early on because they don't want to join the "small/weak" chapter; but those who stick with us learn that we may be small, but we're not weak! The big challenge we face is getting PNM's to accept invitations to round 2; beyond that, it seems that they tend not to factor size into their decisions as much.
(btw, that year that we returned for rush with only 10 women - we doubled in size
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