Probable still a little early to talk about variants, but just to throw some very early idea out there:

Steroid Froglet - Have 2-3 "Steroid" frogs which will be able to jump over 2 frogs at a time. (To be used once then converts self to regular frog)

Fat Froglet: 3-4 "Fat Frogs" which can not jump another piece, but are worth more points when you jump them