It's too strict. I pulled those examples because they aren't even absolutely necessary for what they lead directly towards.
Meteorology is not necessary for the physics of rifling. Having to research everything with an arrow leading towards a tech is annoying. Perhaps you could do something similar to the original tech tree and have certain later technologies require earlier ones, such as meteorology? That way, you don't get too far ahead, but you aren't learning to dance in order to build tanks.
I don't think this is in keeping with the nature of the mod, or for that matter the game in general.
Civ is about building a
civilization, not an army (or for that matter a dance troupe). The entire purpose of the game is to be growing your civilization in multiple ways, so that it becomes systematically better over time- not to stay stuck in the Dark Ages in terms of economic and political structure, and impoverished in terms of culture, while somehow turning into a military supermonster. That is a deeply unrealistic, anti-historical thing.
In real life, powerful, successful civilizations succeed in multiple ways. To take an example- the British ruled over India for roughly 200 years; how did this happen. In Civilization terms, the British had many advantages.
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Ships: the British could sail to India, the Indians could not sail to Britain. This gave the British the freedom to engage or disengage with any part of the Indian subcontinent- if the ruler of one city drove them out, they could simply pack up their bags and sail to another one. No Indian ruler could actually prevent the British from bringing gold, troops, and influence to India
as a whole.
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Resources: the British had a global empire and the beginnings of the Industrial Revolution at home. They could produce all sorts of goods, including things that no Indian had access to.
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Organization: India at the time was ruled by a decaying Mughal Empire in the north, which was so fallen-apart that it actively sold off tax collection and law enforcement rights over whole provinces to the British East India Company because they needed the money. And a large number of relatively small city-states and principalities in the south. No government in India had the strength to stand against the East India Company alone, not when the Company could simply ally with one local power bloc against another, play them off against each other, conquer the loser and co-opt the winner.
Meanwhile, Britain had a unified Parliament that could set laws and policies which gave the Company a very secure base and niche in the global empire Britain was building at the time. And the Company itself was much larger and more organized than any trading concern India had ever seen before. In short, India was disorganized for a number of reasons, Britain was organized.
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Weapons: this was actually one of the least important factors. Sure, the British had muskets and cannons, but so did the Indians, and by and large the British muskets of 1750 weren't obviously superior to the Indian muskets. About the only difference was the scale of production- Britain had dedicated arsenals turning out large numbers of reliable-quality weapons, where India may have had more trouble supplying its armies.
Now, in Civ IV, modeling a conquest like this is tricky but possible. But you'll note that what the British did NOT do is deliberately neglect all their economic and social stuff so that they could concentrate all their energy on war.
No long-lasting major civilization has ever done this. There are barbarian tribes that concentrated on war, but they never managed to rule for very long without being absorbed by their conquerors. Huns invaded Europe and took half the Roman Empire- but lost it again in a matter of a few short years. Mongols spread out over most of Asia- but broke up into squabbling principalities and soon assimilated and went native in China, Russia, and the Middle East.
In Civ IV, most of the technologies don't just represent being able to make a specific thing. They represent institutions, the facilities to make things, the doctrines and techniques that tell you how to use them. And in general, when one civilization triumphs over another in real life, it's
not just by having a few cool toys the other side doesn't. It's by having an across-the-board advantage in many areas.
Modeling that well requires a tightly interwoven tech tree. Because otherwise you get bizarre impossibilities like a bunch of primitives who can't print books and haven't got the hang of not emptying their chamberpots into their drinking water... but who have inexplicably figured out how to build tanks and jet bombers.
Build, in great quantities, too- not just buy them.