If you know what you're doing you can always make use of stuff like CheatEngine, Save Editor or the in-game console. I did try it with Save Editor and gave myself 1000000 levels but it just became boring.
You go in GrowthRPG/Saved/SaveGame, get the save file that you intend modify, and then drag-n-drop it on the Save Editor page, then it's just a job of actually figuring out which of the 43 PAGES of variables is the one you actually wan to change without breaking the rest of the game
