Is this while keeping the population poor through high taxation?
Though I agree, you can make bank as a tiny island and still have your population getting their everyday needs met. It's kind of ridiculous, especially since this was a time of economic turmoil pretty much all over the world (European economy was in crisis early game, then it boomed with the industrial revolution, and then it hit a recession in the late 19th century, for example).
Luckily, Paradox has really honed down on the ability to spend money in CKII and EU4, so hopefully, there will be a lot more expenses to make your nation great.
Honestly? It doesn't matter. Ten years after the game start in vanilla, regardless of how I set my financial settings, I'm swimming in endless amounts of cash.