I'm not 100% sold, since if you have the tech pre-requisites, then it doesn't make sense for a tech to be arbitrarily harder than all the stuff leading into it just because it's in an abstractly defined "new era". I know this is a balance thing, but I always strive for things that achieve both balance and logic together. Ideally to me, what would happen is a really uneven level of development would mean that you develop techs before you have the civics to deal with the fallout of those techs, causing domestic instability - that is, getting ahead introduces new problems rather than exacerbating old ones, and getting ahead in an unbalanced way mitigates your ability to handle it. But that might be too complex for the layman's tastes. Especially when those problems start taking the form of popular will, and the game has to simulate what your people want and how you are going to give it to them. Expansion of how cards are restricted by government, and the legacy cards, would help with that. Right now, very few cards are restricted to only certain governments, and you only get one legacy card per government tier. If you have fewer base cards to pick from and more cards available only to your current or past governments (or even cards that depend on both, eg cards that are only enabled if you are or were both a monarchy and democratic) then they might feel a bit more permanent and consequential. Possibly also make legacy slots that must be filled and can only be filled by legacy cards, to make your past choices even more permanent and not skippable by putting in +GPP per turn cards. You could still have multiple cards granted by each government or whatnot, so you have some choice, but they wouldn't be completely bypassable, and maybe harder to change once you pick - your legacy is your legacy, after all, and it's hard to adjust the narrative. ...drats, now I really want that.