For example, would kingdoms have the basics such as a balance sheet, would they give tax breaks or subsidies to local businesses, invest in infrastructure without the expectation of using it for warfare. Some empires had a debased currency to my knowledge. Did they have monetary policies (e.g. Adjusting late payment fees of local banks)?
Ok, first things first: European kingdom were not states. Even the most minimal definitions of state (monopoly of legitimate use of force in a given territory) can apply to polities bigger than cities or fiefs only after the Peace of Westphalia. Before, kingdoms were a very, very loose network of polities whose only obligation toward the center/king was customary and/or personal.
This reflected both in the military aspect (kings did not call subjects at arms or raise armies, they summoned lords and cities to bring their armies and fight for them) and the fiscal one (kings did not directly collect any tribute, they demanded parts of the ones collected by lords and cities). Even for coinage, whilst in some areas there were a central mint since the late middle age, in most of Europe was mainly carried on by local authorities with the gold of private citizens, and hundreds of different "currencies" coexisted in the same kingdom.
This all changed in the early modern period, with the rise of the fiscal-military states, that is, polities that for the first time in history had sufficient authority to directly collect tributes. However, although in the most dynamical proto-capitalistic areas states absolved some of the economic functions of the modern state (for example, Venice issued publicly-backed guarantees on bank deposit), and invested in "research" (many of the explorations of the Age of Discoveries were publicly funded), most of the budget went into the military, with very little left for anything else. This is one of the reasons why, contrary to common intuition, the decline of feudalism in favor of a more centralized and modern state caused a rise sharp in both income and wealth inequality (due to the fact that taxation was extremely regressive and public expenditure either wasteful or useful only to the very upper class).
If you are interested in (public) economic history of preindustrial Europe, a very up to date and nicely written book I incurred in recently is "The Lion's Share: Inequality and the Rise of the Fiscal State in Preindustrial Europe" by Alfani and Di Tullio, Cambridge University Press, 2019