Here's my beef with the current system:
Even with the nerfs to limit development in the recent 1.13 beta, the core problem has remained. That is, AI or player development in a given set of provinces does not come from:
a) inspired leadership
b) abundant resources
c) smart investments
d) any kind of "social" or outside pressures
No, it comes from countries unable to expand and sitting on their asses clicking the improvement buttons. All this meaning that the largest metropolises arise in something like Luxemburg instead of a Milan, Rome, London, or Paris, etc.
There needs to be something else to represent actual resources poured in to improving a province, as well as other organic limitations (such as too much density or scarcity of resources), because monarch point income is totally divorced from anything directly representing population, production etc. Other solutions such as a cooldown timer and/or monetary costs are a fair start to stopping the rise of ridiculous OPM metropolises.
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One idea I had, (and that I think should be considered) was that instead of having linear progression by clicking the same 3 buttons on the interface, there could be a whole new "development" panel somewhere that works similarly to buildings, and gives everyone the same limited number of small-to-moderate sized boosts to development values. It could be stuff like +1/+1/+1, or +4/+4/+0 as a lategame boost, or even something like -1/-1/+4, or any conceivable combination with the numbers balanced as we go on. Ideally each boost would have a different monarch point cost associated with it (equivalent to maybe 1/4 or 1/2 the cost of an idea slot), as well as a monetary cost, and optionally a cooldown/construction timer to limit mass improvements.
The boosts would represent the implementation of new top-down government policies (maybe abolition of serfdom), the presence of conditions that allow arts/trade/manufacturing to flourish, or the abolition/supplanting of old ways of thinking.
Also, since everyone can pick from the same set, the total amount of development available has a hard cap that is in line with the maximum achievements of the era. This way, some sorry mountain province like Waldstatte is pretty much guaranteed to never overshoot a major starting capital or farmland/grassland provinces that are better suited to development.
As an additional limiter, certain boosts can have certain buildings or government types/rank as a pre-requisite, which means a soft tech-limit (e.g. one boost requiring barracks while another requires training fields, or a certain boost requiring a government type enabled by "The Enlightenment"), as well as ensuring that capitals/high development/good environment areas can't get overtaken by OPMs in mountains/highlands/marshes.
Lastly, perhaps to represent certain nations making an active and purposeful decision to commit to development, the Economics idea group finisher could possibly change to "+1 building slots per province" to allow these dedicated nations to explore the development boost tree farther than they could otherwise based on building requirements.
Beyond the balancing of numbers, this should be easy to implement as it would mimic the building interface, and could even take the place of the current development panel on the quick-build menu, albeit with a different look.
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