Yeah, my sentiments are essentially the same as WeissRaben; How exactly is the current system free from these issues while mine is especially vulnerable? I have placed limits on the player in the form of the scaling cost of Ideas, and by introducing a conscious choice between specialization and diversification which currently pretty much doesn't exist.
You asked, I think somewhat hypothetically, why a country wouldn't just invest straight into the direct bonuses; +Production Efficiency, +Trade Efficiency, +Discipline, and the answer is the same as now; Because there are other things that are more cost effective for their situation.
I mean, why would you invest in Production Efficiency unless you already have some high Production Value provinces? If your country is entirely based on Low-Tax Grain Provinces, you won't get much out of a fancy idea that gives +5% or whatever PE. The Berber States and other countries in such a situation would profit more from other things, like Trade or Piracy focused Ideas. Ultimately they might still invest in some PE eventually, and why is that a bad thing? Pretty much every country developed all of the areas a little bit at least, some will specialize, others will be more general. My system lets you have a passing interest in Production Efficiency without going into it whole hog.
And say some country does invest in all of the straight bonuses, ignoring for a moment that this would be wildly expensive in terms of Monarch Points since each Idea increases the cost of All Subsequent Ideas including Ideas in different categories, why is that a bad thing? They'll wind up with a very Tall Nation, that dominates its area, but cannot expand much beyond it. Take Trade Efficiency. Okay, you've got a ton of Trade Efficiency, good for you. You don't have many Merchants, so while your Provinces Trade like Gangbusters, you can only extend your reach into two other Trade Areas. Meanwhile a country that Invested in Merchants and skimped on the Production Efficiency can trade Around you, even if they cannot trade through you.
Currently, that choice doesn't exist. There is only 1 Trade Idea Group, and all of the other "Trade" bonuses are just tiny ideas scattered around in the other groups. The only way you can specialize in Trade is via hand-me-downs from other Idea Groups, and by picking Venice at the start of the game.
As for Discipline, why would the same factors not apply? Russia will be more interested in investing in Quantity than Quality, Prussia will be more interested in investing in Quality. Although Personally I don't understand why anyone would ever choose an option that wasn't max discipline, to each their own.
I don't doubt that pretty much everyone will invest in some level of discipline, much like Production Efficiency. That makes sense, and its entirely historically accurate, everyone tried to have a disciplined fighting force, some just did it better or had more resources to invest into it. The diversity will come in who does specialize and who doesn't.
For Instance, Austria will be in a bit of a pickle. Prussia can invest in Massive boosts to Quality because they are small and mostly homogeneous, so they don't really need to spend their points elsewhere except maybe some scattered economy related Ideas. Austria on the other hand is a large Multi-National Empire. They'll need to invest in ideas to reduce the penalties from wrong-culture provinces. Russia on the other hand will be in a somewhat similar boat because of their massive Muslim Tartar population, but they can go in the opposite direction and instead invest in ideas to convert them and Russify them.
Likewise, France might want to get involved in Naval Matters, but being surrounded on the Continent by Spain will necessitate some devotion to a Land Army that, say, England won't experience.
And also like I said in the post, ideally we would have the ability to modify the cost of ideas on a case-by-case basis. In a truly ideal world we would even be able to modify how much each idea increases the cost of the next idea the country tries to choose. So if there is some idea that does provide a considerably higher bonus than others we can adjust the cost accordingly. If +10% Discipline costs as much as 2 extra Merchants and a boost to Steering Power, it becomes a bit more difficult of a choice, especially for someone who wants to be involved in Trade.
EU3's system wasn't balanced, Okay. My system isn't EU3's System.
@gsabram: I was thinking, if there is any sort of Idea Tree, introducing "Dead End" paths that could provide considerable short term bonuses but not unlock, or negatively impact the cost of later ideas. For instance, you might be able to invest in Heavy Cavalry that revolves around the concept of the Knight, but then that wouldn't translate to a Modern Gunpowder army as well.