I was at prestige layer 5, AND with points in exp+dmg + base multipliers, now I am barely getting back to layer 4 getting stuck at floor 50 instead of floor 84, the nerf is terrible.
In addition to it giving you more money for selling T5, you can click really fast to sell the same thing multiple times, got like 2M in a few seconds with an autoclicker.
The reason you're falling back prestiges is your current EXP has to be the amount specified, so if you buy something and go down from 100 to 90 current EXP you'll drop from Bronze II to Bronze I, this should be fixed.
Maybe you should add an option for automatic compact numbers instead of manually having to set them, for example if you reach 1 million it automatically starts counting with "M" and if you reach 1 billion it starts counting with "B".
I'll speed progress up in the next update :) Thank you for your suggestion! :D