Only the leftmost girl's design doesn't get reused, it seems. Aside from Molly herself, the guy looks like Hisao w/o ahoge (granted, Hisao isn't exactly distinctive) while the rightmost girl is a dead ringer for Shizune (only Shizune don't have purple highlights).

Astana said:
Only the leftmost girl's design doesn't get reused, it seems.

There's a couple of sketches with her. I won't post it out of personal taste.