Terrain, every province has a different terrain type, which influences many things related to such province, like defensiveness, movement speed and dev cost, grasslands don't have any dev cost modifier and farmlands even give a reduction, any other type of province will give some kind of cost increase.

Idea Groups (Quantity + Economic is the perfect combination for deving, since the dev cost reduction of Economic can be combined with the dev cost reduction policy given by having both Quantity and Economic ideas at the same time, it's advisable to take Quantity first and Economic second, since admin points are required both to take Economic ideas and take Administrative tech, which unlocks idea groups, taking Economic as the first Idea Group can delay taking Quantity by some years) In order to reach the efficiency necessary to achieve this ratio in all (or most) controlled provinces, there are some conditions to be considered: The military development is more obvious, since it directly influences manpower, which also receives tons of modifiers, but, in this case, there's not even a choice, since manpower can only come from the military development, which makes it arguably the single most valuable category in this entire aspect.ДЄs such, the ideal ratio of development for any province is 1 Tax, x Production, x+2 Manpower (+2 since you can dev up to 1 more point than the combined value of the other two categories), which, once it's considered that, generally speaking, deving is most efficient up to 20-21, the ideal ratio would look like 1/9/11вЂ¦ with the same adjustment being made for any other size (like 1/4/6 for an 11 dev province of 1/14/16 for a 31 dev province). Well, first of all, administrative points are better spent on coring provinces than on developing them, second, administrative development is related to the tax base, which only gives you tax income which doesn't have many modifiers that help it grow, while, on the other hand, diplomatic development is tied to the goods production, which is also directly related to the trade income, the amount of modifiers that can influence both of those income sources is very big and increases progressively all over the game, which means that a well developed nation can easily have most of its income coming from production and trade. This can be achieved through the right combination of ideas, policies, buildings, privileges and other modifiers, some of which are temporary, the key is then to exploit a time window on which dev cost is reduced to its minimal expression, while you have a surplus of power points, specially diplomatic and military pointsвЂ¦ вЂњwhy diplomatic and military?вЂќ you may askвЂ¦ The Dev Cost Meta, briefly explained, consists on stacking various modifiers that reduce the development cost of provinces, with the objective of facilitating higher levels of income and manpower base, since both values are closely tied to the development of every province comprising a nation. The answer to this question comes in the form of a particular technique known as the вЂњDev Cost MetaвЂќ.

Yet almost every player has come up to a point where they wonder: вЂњHow can some players get those incredibly strong nations?вЂќ A question that becomes even louder once the top tier competitive MP games are discovered, where nations comprising sometimes not even more than 4-5 regions in Europe are capable of fielding hundreds of thousands of soldiers and have millions of reserve manpower, all while keeping a healthy balance. (Image form my Mewar > Rajputana > Bharat run)

India can be a nice land to conquer, but it's also excellent to dev.

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