Nobody tells you that money stops being about money somewhere around the point you have enough. After that it is entirely about sleep. I have been broke and I have been comfortable, and the difference in my happiness was almost nothing. The difference in my sleep was everything. So I stopped optimising for return and started optimising for the ability to stop thinking about it.

Keep enough set aside that a bad month is an inconvenience and not an emergency. That is what wealth actually buys.