Some things I noticed immediately upon trying this mod:
Building an iron mine (low yield) adds only +75 wealth, but costs 8250. I started a campaign with Denmark and I can build one in Norway (50% taxes with medium tax sliders) but it would take 220 turns to pay for itself. This is a somewhat extreme example, but with no offence meant, the balance of economic buildings I find to be extremely bad. Buildings which contribute fixed wealth are just not viable and even those that contribute growth will take a long time to pay for themselves. If this is intentional then I guess fair enough, but why not simply remove the buildings from the game then? Surely it's just a handicap for the AI to have economic buildings function as money sinks?
The education costs are quite massive. For most of the countries I've looked at, they are just not affordable--e.g. on Hard Denmark needs to pay 3,000 per turn for a School, but even with all trade routes used and taxes at the highest level, does not make this much money. I guess it's possible to maintain the School if you conquer some provinces, but not with Denmark's starting territory. Major powers have it better, but the costs are still huge. Given that the AI is very reluctant to trade technologies, is it deliberate that minor powers have essentially no access to technology? If so, why bother making them playable?