It's not a question of State Property being really powerful or anything... it's just an option. It has it's pluses and minuses like any other civic (with the obvious exception of Decentralization.)
The way you put that caught my attention. None of the default civics are great, of course. But in my opinion, Decentralization is a lot LESS bad compared to Mercantilism (WITHOUT Representation) than Despotism, Barbarism, or Tribalism *compared to* other options in their civic categories. Note: I'm not saying it's good, just less bad than those civics, compared with *their* alternatives. I'm not sure but maybe Decentralization also wouldn't be too much worse than Free Market if you have a small empire, can't get consistent Open Borders and peace with accessible civs, and you don't have your own overseas holdings or vassals. Of course the longer the game goes on, the more you are likely to acquire those things, or enlarge your empire and the populations of your cities (increasing trade
).
To look just a little more at Merc (which Decentralization might perform closer to than FM even with limitations): you have to go through at least 1 turn of Anarchy unless you are Spiritual, replace all foreign trade routes with domestic ones, and pay Medium upkeep instead of Low. It can take a little while for that to pay off. It probably pays off faster if you have another civic to change at the same time.
Given the strength of the widely-favored strategy of researching the "upper half" of the Medieval/Renaissance tech tree and trading if possible for "lower-half" techs like Banking, I'm glad Decentralization performs as well as it does. (Plus, its decent performance vs. Mercantilism *contributes* to the strength of that strategy. Imagine if Merc were much stronger than it is--might change the cost/benefit balance somewhat...) It does, IMO, end up looking a little odd if you have, say, Representation, Bureaucracy/Nationhood, Slavery or Caste, the religious civic of your choice, and you're still in Decentralization because you don't have Banking. (I know we might not get all of the techs (and/or Mids/Shwedagon Paya) for those civics before Banking on a regular basis, but my point is that it often takes a lot longer to unlock a non-default Economy civic than non-default civics in other categories).
I've left Paganism until now. It's the only Low upkeep religious civic until the "latest" one, Free Religion. Pacifism has no (official) upkeep, but it can take a while to get Philosophy, and really Pacifism's upkeep is what it costs you for your military, so the true cost of the civic scales up with your military. And getting a benefit from any non-default religious civic requires having your state religion (or, of course, any religion in FR, the more the merrier) in every city where you want to benefit (except I just realized, you do get +10%
in all cities with FR; still, it comes later than the other religious civics).
Anyway, it makes sense to me to not declare a state religion and remain in Paganism until I decide that the benefits of adopting a religion outweigh the usual diplomatic hit with at least 1 civ, often more.
I didn't intend to write so much. Perhaps by "the obvious exception of Decentralization" you just meant the other Economy civics are better; if so, I would agree. But the other default civics, except Paganism unless and until the time to adopt a religion comes, seem way worse to me.
with minimal infra requirements), and FM with corps can compete. Your choice is a function of your current tile improvements, intended victory condition, and how far off the win is.
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