For what it's worth, I wholeheartedly agree that spies*acres^(-1/2) is superior especially for balancing. It works out in such a way that the proportional spy expense between two countries increases at the same rate as the proportion between the marginal benefit of running a turn on two different countries with the same % of indy sites producing spies. That is not true with spies*acres^(-1/3) and I feel like it should be. I was just pointing out that it is easy to change the formula depending on what should be balanced (that's also why I asked if it is arbitrary).

Sorry if that sounds confusing Lol