>>528369586
Get to hard mode with Ult Bunny and catalyze her ASAP. Try to go for a build like this, prioritize HP and then Range/Singular/Electric as secondary. Farming these modules is way easier on hard mode as well. Normal is pretty much a story + tutorial, the true bulk of the gameplay is in hard mode grinding.
As for who to unlock, probably Serena or Ines since they're meta or Kyle/Jayber for the memes. I have builds for them if you want as well.