I have an idea to reduce the lag. Disclaimer: I don't develop games, but have written programs to calculate models, and they lagged due to too large numbers.
OK, so you have pockets (list or whatever you use), for each multiple of 1000. So if you have 1,000,876 money, you put 1 in the M pocket, 0 in the K pocket and 876 in the units pocket. Note: if you have 999 and get 1 more, you have to empty the unit pocket before you add to the k pocket, otherwise you'll still lag.
This cuts out calculation time (at least it does in Python).
I hope this helps because I really enjoyed the game.
Hi, thank you very much for your suggestion. I wrote you a private message regarding your comment because my answer seems to be too long for the comment section. :)
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Hi, thank you very much for your suggestion. I wrote you a private message regarding your comment because my answer seems to be too long for the comment section. :)