Guess that means I better get on claiming a rainbow before the deadline comes. Probably Sakura Swim for crit+weakness or Tall Stewertia Christmas ver. for her awesome crit and because she is overall just awesome...but I'm curious what (if anything) they would be replacing for the RC currency/shop area?

The Earthworm grind, for someone just coming back from hiatus, seems not too bad at all. My crit team usually 1 hits the bosses; but the odd time the boss goes first messes me up a little bit. Like Maotd said, the shortness of the lvl + some variety of lvl layout are good elements. There are certainly worse grinds in this game genre, like Granblue Fantasy and others...haha.