I do see what you mean and it played into the thinking in the design. There's 3 factors that weighed in you might not have considered. 1) The game isn't ready for you to have the kind of power you'll get from a tier II or III trait before they become available. The values assume a certain level of development has taken place before you can take these kinds of modifications without balance being more upset. AND 2) Something has to deter the obvious strategy of using traits to pump more culture to pump out more traits overall, without wanting the culture as a benefit for its other reasons. AND 3) The earlier you get a trait, the longer it influences your output, the more impacting it is overall in the game.
1) Do you mean that the Tier II traits are stronger in absolute terms than the Tier I ones (and therefore it would be problematic to allow some civilisations to get access to those traits earlier than others) or do you mean that they would synergise excessively well with an undeveloped empire if you were allowed to take them early?
If you meant the former, then we run into the issue I was bringing up - that if you build around culture you end up with worse traits than if you didn't. On the other hand, if you unlock tier II traits after a certain amount of culture - say you get access to them when you get your fifth trait, or whatever the appropriate balance point is to make most civilisations get it from their first renaissance + trait - then most civs will get their tier II traits at the "correct" stage of the game, and those which get them early are the ones who have invested heavily in culture in a way that would normally have been suboptimal. Which seems to be the general approach you were aiming for in designing this anyway - that you have the strategic option to pour commerce, buildings, etc into culture in a way you normally wouldn't.
If you meant the latter, then firstly, I'd point you back to your own arguments about why preeminence isn't overpowered just because it's strong early game. And secondly, would you mind giving a few examples of this? I'm struggling to see how the higher tier traits are unusually useful in the early game compared with the late game.
2) Why does that need to be stopped? You can build production-enhancing buildings, or research improvements to research. If you're spending your first trait on something that enhances your culture so you can get more traits, you're not spending it on something improving your civilisation in other ways, which could themselves be used to enhance your culture and/or the other aspects of your empire. And I don't think that spending a trait
just to get more traits is going to be a good strategy at all, due to how the costs scale. You'd have to have the trait single-handedly multiply your overall culture gain by 10 just to break even! In fact, the only reason to even consider doing such a thing would be if the later traits were more valuable than the earlier ones, such as in the way I'm proposing. And even then it would be a case of sacrificing most of a trait in order to get access to the higher tier traits sooner.
(Maths note: If you didn't care about culture for anything else - the scenario you suggested - and the trait, say, doubled your culture, then for about 4/5 of the game it won't actually be giving you anything at all for you, as you'll have the same number of traits as you would have normally,
including the one you used for culture. And during the remaining 1/5 of the time, you'll have one more trait than you would have otherwise, but you spent one of those traits on improving your culture which you don't care about outside this calculation. Thus you'll spend about 4/5 of the game effectively down one trait, and 1/5 effectively breaking even - a terrible exchange if you aren't getting more advanced traits in return, and a dubious one even if you are.)
3) True, of course. But there's more than one way to restrict things to later in the game, and requiring you to have earned a certain number of traits (ie gained a certain number of points of culture) before unlocking higher tier ones will provide a delaying mechanic just as well as restricting by gateway techs (which, after all, is basically just requiring you to have gained a certain number of points of research).
Edit: I've just reread your point, and realised you might have been saying that the long-term weaker trait arrangement is part of the cost of getting your traits early. But that's a bit of a red herring, isn't it? The (fairly significant) cost for getting your traits early is that you have to pump culture, at the expense of other things! Of course if you choose to focus on unlocking new traits quickly, they'll have more impact on the game. The same is true of technology, of building, of units (especially units - not much point having an amazing doom stack that will be ready in 100 turns if your enemy is attacking your capital right now!), of great people, and of pretty much everything else! It's a fundamental design element of civilisation, and most other strategy games: what do you prioritise in order to start getting the benefit from soonest?
I know I still need to open up limitless national culture amounts earned. And I know that it seems like it would take so much culture you couldn't possibly get too many tier II and tier III traits, even less the more you got in tier I. However, the synergistic benefits, even crossing between differing types of trait strategies, can be as or more powerful than the mere improved degree of stats on a tier II or III trait.
For example, combining spiritual with glorious - sure it's obvious right? More frequent GAs from Spiritual from Prophets born, with longer and stronger GAs from Glorious to counteract the GA length penalty of Spiritual, is more powerful in combination than either trait is alone, by far. Then, crossing into a whole 'nother category for playing on that same type of synergy, Strategist also adding more GAs from the birthing of Great Generals, then another trait to help you get more great generals, then another to counteract the penalties from what you've accumulated so far and so on. Blends are strong. Often stronger than the next Tier of a specialization.
That would indeed be strong. However, it would not be particularly strong for my strategy - the golden age part of the trait was only a nice side bonus for me, and it was the "benefit from having lots of religions in your empire" mechanics that I chose the trait for. Now I'm not trying to make this into a demand for my personal strategy to be catered for, but this is an example of how
some strategies work fine with a culture heavy strategy, while others - the ones which rely on only one or two traits - don't work well at all.
Also, haven't you rather undercut your own argument 1 from your first paragraph? If blends are often stronger than a single Tier of a specialisation, then how can it be OP to allow higher Tier options instead of blends?
I need to go, so will address the rest of the post later.
