This is a fair point, and rhymes with other commentators’ feedback. I could have started with `Obligation -> Debt -> Money`, for example, and that strikes me as a better beginning. People need money to pay their debts, and this theme would re-appear at various levels of the hierarchy: the villager needs stones to pay taxes, the village needs black money to pay tribute, and so forth. I think this would add meaningful nuance to the "just so" motivations; money isn't solely motivated by trade but also by social obligations and political power.
That said, I would not find a full Graeber-ization helpful. It wouldn't change the structure of the post, and I don't think Graeber's framework is useful for understanding much of the content, such as the Fed funds rate, the intra-bank clearinghouse, or correspondent banking.