Inflation Model
The game doesn't require a more complicated system, it requires a simpler one.
Inflation in a nation operating on a gold standard (on any fixed exchange rate regime) doesn't operate anywhere close to the way it does in EUII, and as such I consider it the most frustrating and weakest part of the game. Inflationary periods before the widespread adoption of printed money occurred when the government chose to print money to cover short-term high expenses (such as war) or when the supply of gold/silver increased substantially. However, in both cases inflation subsided after the supply of money decreased again (whether the amount of gold being shipped from the New World or from the readoption of the gold/silver standard after printing money). Instead of governors controlling inflation (which I don't understand), inflation should just decrease naturally over time towards 0. That way, inflationary periods would occur when new mines were found (this would require mines to become useless over time - or to cease increasing inflation past a certain point), or when war/disaster necessitated printing money (which I guess is approximated by taking loans even though they are essentially two separate, and essentially opposite responses since printing money is just a discrete tax). Then when things were more stable, deflation would set in as the country exported its inflation and its economy grew to provide more goods for the same amount of money. This would much better approximate the historical behavior of inflation and also make it possible to actually control inflation in a country that doesn't have 30+ provinces.