When I recently played the Nubian demo, one thing that really caught me off-gaurd was the ability to change cultures so quickly and easily at era changes.  When my Chinese foes suddenly became Greek, it was also actually really story-breaking.  One minute you know someone, the next you don't.  While I really like the idea of cultures blending, shifting, and layering over time, it would seem more in keeping with human history to have these shifts either be gradual or when the occur suddenly to bring some about of instability or stability, based on what state your civilization is in at the time.

One place to start would be to only allow certain "close" cultures unlock, based on the choices you've made in moving the ideas bars (I'm forgetting the name of this section, but those various scales that move back and forth, effecting political and economic bonuses and such).  You shouldn't be able to move from a culture that leans one direction to one that goes to the opposite extreme.  Or, if you were to allow that, there should be penalities and instabilities created by the drastic departures from the existing culture, much in the same way that there's kind of a legacy bonus (am I remembering that right?) for keeping your current culture.

An even more advanced mechanism would allow for dramatic culture shifts when your civilazation is not faring well.  Perhaps they are being outcompeated for religious dominance, cultural expansion, or some other measure of "superiority" of another culture.  In that case, it would make sense that shifting to a culture closer to the dominating force would be easier to do and confer, perhaps, economic, diplomatic, or religious benefits.  Perhaps if you are really loosing a war badly, cities aren't growing, or you are falling behind in technologies, drastic shifts in culture would be easier to do or provide some extra bonus for change.  But if a civilization is stable, happy, prosporous, the forces of "status quo"/not shifting cultures would be higher.

In some of the orginial descriptions of how cultures worked in Humankind, it seemed to suggest that you built your own culture over time by combining various elements from the cultures that had existed through the ages in your civilization's development.  I didn't get any of that kind of experience in what I saw, which was disappointing since it seemed like an amazing idea, in keeping with human history, and leading to greater customization and story-telling experience.

The kinds of tweaks and mechanics I touched on, would help get back to that kind of cultural development and lead to the addition of creative and realistic elements in human history like cultural appropriation, assimiliation, and other ways that various cultures have come to occupy the same spaces and peoples over time.

One more suggestion for drastic cultural change penalties - what if you lose outlaying territories or cities that don't want to change to the new culture?  Or perhaps major cities in the interior rebel under certain conditions and you have to reconquer these lost areas, or meet cultural (or other) "superiority" marks that convince them to "convert."  Maybe you can send settlers or expend diplomatic resources.  Lots of options, but there should be a way to check what the likely outcomes of cultural shifts will be so that you can set up conditions for change before making shifts or weigh benefits vs consequences readily.

Cultures in Humankind are largely divorced from civics, so shifting based on that doesn't make sense. Cultures don't really have a "closeness" to each other, so switching to a "closer" culture doesn't make sense either. Since switching to a new culture is a form of advancement, doing so on falling behind will result in players strategically manipulating it to fall behind by the game's measure enough to switch, without actually losing that much. That said, there are already catch up stars you get when you fall behind other civilizations.

cjmpathfinder wrote:
In some of the orginial descriptions of how cultures worked in Humankind, it seemed to suggest that you built your own culture over time by combining various elements from the cultures that had existed through the ages in your civilization's development. 

That is reflected in several ways, the main one being Legacy Traits that are unique to each culture and you keep them even when you switch off that culture. So after taking a Classical culture you still keep the Nubian Legacy Trait for example. Other aspects are your Emblematic Quarters and non-Upgraded Emblematic Units that you built persist, as well as City Centers which keep the appearance of the culture that founded them.

It's not as uncommon as we might feel that cultures drastically change in relatively short timeframes (historically speaking ofc).

It's also a game that gives us freedom to change a peoples identity along the way most will probably change into a culture that fits their circumstances at the moment they are able to, or to achieve a long time goal. For me it's not immersion breaking, but I guess that's personal taste.

I feel like this will be an alien concept just a couple of first playthroughs and will become more natural with time. I dislike the idea of any turbulence on culture switch, it sounds logical, but makes me think that it would hurt the gameplay in the long run, though maybe it would be interesting incentive to keep your old culture and make switch more rare and more special. Definitely not a fan of idea that only 'close' cultures should transfer into each other swimmingly, putting aside that simply not enough cultures are available and you can even end up in a cultural 'dead end' in some eras, it also means that people late to the switch will be additionally punished with turmoil picking the culture that was left for them.

Mixed feelings about whole concept, but in the end I think I'm against it. This is a sound idea for a mechanic if radical culture change would be something special that you could do, but with how common it is supposed to be I think it would just add unnecessary busywork. Would be different if there were hundreds of cultures to choose from with every era, but that would also eliminate a 'racing' element from whole system. Honestly, I hope that if/when additional cultures drop, there will be an option to limit the choice every era, so that some just won't be available in that particular playthrough.

There is already a "penalty" on switching.  Once you switch, you leave the Era you are in and can't earn any more fame in that Era.

In the end Humankind is but a game. And since it embraces this 'alt-history' feel, why not go full speed with it and have bizarre, in our perception, changes? After all cultures, when disconnected from their Earth background, represent a set of social, economic and worldview values. So it's not like nubians suddenly change from african to south american when shifting to mayans. It shows how culture changed into one reminiscent of this known to us.

Another thing is the length of a turn. It is really funky to measure time in discrete units and why not just say that the time between culture changes in one turn is enough to have transition seem seamless?