I don’t understand what you’d exactly want.
(I guess the JUCE team would clarify or correct me if I’m wrong).
If you WOULD release your source-code when asked (or provide it), then your can go GPL not requiring anything else. (even if you charge money for it, as long as your code will be exposed when asked or provided).
If you would NOT release your source-code and keep it closed, you simply comply to JUCE Personal limitations and that’s it (as long as they comply / you’re revenue is within the terms described).
This is regardless of profitability in your case since if you “sell” the product for 0$ then 0 < 50k always…
But if you’d like to opt out of sending analytics of your users to 3rd party (JUCE…) or having a splash on start then you need to shell out money.