Well, I don’t see how your SQL expresses your previous idea. Positional statistics that I see in your SQL query are tricky to get right, and in general wouldn’t express any specific probabilities.
In any case it seems you want to make having a single wallet slightly advantageous over having multiple wallets: not enough to have a significant rich-get-richer effect, but still one that prevents operators from having many small wallets. Is that correct?