Yeah, completely removing the ages I'm pretty sure is a non-starter from a design perspective. I mean, sure, it's not impossible to just chain together the tech and civic trees, for example, and probably to have 9 tiers of units instead of 3x3. But you'd have to redesign the whole overbuilding system, add in resources appearing or disappearing somehow, never mind figuring out how that completely different game from the classic game balances with the classic view, including making sure each civ's unique trees make sense and show up at the right time (you'd need to make sure the American Rail Yard doesn't get unlocked 20 turns into the game, obviously).
My solution for this is to flatten all yields and not have yield scaling.
Right now, IMO, the problem with Civ 7 that makes it boring is specifically the balancing around hundreds of different bonuses that affect yields, and a highly oversimplified adjacency and specialist system, along with yield scaling meant to allow behind players to catch up. This balancing constrains gameplay into narrow and repetitive choices, and some have described the choices in the game as too "spreadsheet-y" which is funny for a 4x. Usually a little spreadsheet-iness is appreciated, but here there's nothing outside of yield maximization, which ultimately does lead to snowballing and a dead endgame. What I've found, in fact, is that spawning with just the right resources nearby seems to make all the difference in your early game that sets up an inexorable snowball. This core emphasis on yields and balance is what makes the overall age structure also repetitive and boring.
Like I said, my solution is to flatten all yields to small, narrow range, and replace yield maxxing with asymmetric strategies from synergistic civic and building effects. An example would be a building that generates culture based on the number of players whose trade routes cross that city. Or a building that generates science based on the number of codices assigned, but with a geometric progression for stacking codices (but the building can be looted).
So, in other words, it's no longer about just building one of that building in every city to stack yields, but placing the right buildings in the right cities based on circumstances. I then proposed an age based "event" system that creates the feeling of an age that age-based civs can relate to, without forcing players into a legacy path progression within this hyper balanced yields framework.
It's a bit of a paradox. By having age-based civs, you actually exacerbate snowballing by overemphasizing the importance of ages. This means you have to nerf the importance of age and make ages relevant to game flow in some other way. I would like ages to add flavor (doing different things in the game at different times) and progression should be measured in adding complexity and more systems over the progress of history, not necessarily through mad scaling and bigger moar numbers.
With the right buildings, you are going to get higher yield if you manage complementarities correctly. Likely, you will also get higher settlement limits, creating scale that way. While there won't be strict scaling (+1,+5,+10 yields for age based science building), you can have soft scaling, where you balance by estimating the range of yields a building can produce, and limit it within an age-based guideline that manages scaling. So, for instance, a factory won't produce hammer yields just on its own, but based on the number of resources assigned. You have to choose specific places for factories, and have the resources at hand, but a factory could potentially produce, say 100 hammers per turn. Developers will reckon the average factory number per 10 settlements, and then create perhaps a range estimate based on resources prevalence on a map, and say that an average factory could produce 20-100 hammers, average of 35.
So you no longer just plop plop plop a factory in every city you can once you research it. You might have more settlements and more production buildings (+1-2 average production) to increase hammer yields. However, you strategy will determine the unique places for a factory to go, not in every city, and through these you can achieve substantially higher yields.
That's the idea. I would expect players to find synergies that break the game, and I would think that's a good thing and easily corrected in patches. This process of having a sandbox of conceptually balanced tools, players breaking them, and devs interacting and further balancing is part of what fuels community participation in the game IMO.
