> Which financial models best describe reality in your opinion?

The most-powerful ones for individuals are the micreconomic mechanisms. Understanding how leverage, tranching and moving risk (and reward) across stakeholders and time, work, for instance. The necessary mechanisms and tradeoffs one must make, as well as the ones one should.

If you're looking for a formal model, it's the balance sheet. But not the accountant's. The financier's. Sources and uses, and uses and sources. Payments in, payments out. How do they balance over time; how do they change exposures to different layers of economic and legal control.

The primitives of these models are transactions and people. When you look through them, they're defining human wants and ambitions, faults and fears, patience and mortality.