This was just an idea that sprouted as when you hit the "end game" of Earl the parabolic nature of cost increases means you functionally hit a serious wall at one point, but the arena difficulty (yes, I know I'm the only one who apparently notices) keep climbing. Current testing status :
View attachment 600859
Next plateau goal for me will be to cash in 2k credits at next rebirth. But that will mean around 5 days at current idling accumulation rate.
I do suppose you could also consider the cost wall a reason to push for more frequent rebirths using that multiplier to try to beat the wall for a while.