I'm not sure if 100% modularity is what is needed or available, but that degrees of variability would creare different kinds of gameplay would be appreciated.
From what it sounds like in All Under Heaven, China, Japan and Korea, and Southeast Asia are all going to be receiving different government types, in addition to the release of Nomads in less than a month, to make at least 4 government types. While we lack details, the mechanics implied make it sound like playing as the Jin dynasty will be different than playing as the Khmer, whether that's rules of engagement, different interrealm/foreign interactions, a mana to spend, MAA and warfaring limits, etc. Given how we've been able to enjoy playing as just tribes, clans, and feudal for 4 years before last fall's Administrative government, I think this'll open up a lot of new ways for us to play and interact with the game, with different mechanics in different parts of the world to try out through several different playthroughs.
Meanwhile, in present CK3, the only difference between tribal subsaharan africa and tribal ireland is the men at arms and cultural tradition modifiers. Feudal India is the same as feudal Germany, though Catholics can participate in a Holy War and Hindus can take multiple wives. A clan of Maghrebi Bebers is the same clan as Ghurid Afghanistan. We've played most of these same campaigns already, it's now just got a different coat of paint to it.
Similarly, most differences between religions are modifiers at best -- marriage laws, holy wars, heads of faith, and realm priests are the only consistent "mechanics" that are consistently interacted with. Sending sons to monasteries is just another method of disqualifiying someone from succession, using a different resource. No, getting +5% piety for using the Pilgrimage mechanic doesn't make it different relgious "feature." A custom relgion might make things fresh in the short term, but there are limits on how much the doctrines really affect our gameplay.
I don't mean this to be mean of the CK3 team, data is limited and production times are critical. And, especially, AI logic and optimization is difficult on the best day. Adding a whole ton of complications would not do any good--but the history represented in this timeframe is anything but limited, logical, or optimized.
My personal want would either be for these systems to have different government types that influence different styles of play, such as how Administrative gives so many different affect in comparison to feudal/clan, or ways for Feudal to have variants with actual mechanical interactions to represent different historical representations, so that playing as a Feudal Empire with an Itinerant Court and the Imperial Church has MECHANICAL differences from a Centralized Feudal Kingdom with Gallicanism or a rising Duchy colony with syncretic Missionaries, etc. A failing Administrative Empire with strong regional governors that'll split into feudal states versus a bureaucractic juggernaut whose influence will become adopted by all who take over its cities. Does a lord only answer to his council, a senate of noble families, a parliament of powerful lords, or a diet of all of his vassals? Do the clerics have any say in governement, or the actions one can perform, be it diplomatic, warfare, or internal? What about cities - are republics really a thing other than money pots, and what about their historic rise to prominence via the commercial revolution?
Roads to Power gave us plenty of new mechanics that influence gameplay and playing around with/affecting mechanics gives more options and variability than +10% Levies from Patrilineal Vassals on Tuesdays.
Let AI behavior be driven by traditons and with new affects that can be unlocked over time through innovations -- things that a liege would want, things thar a vassal would want, things that a head of faith would want, so that an England formed in 867 is not the same as England still played in 1452 (without becoming Administrative)
Look at the data: collected before RTP, and so no Administrative governments, and there's no differentiation between start dates either, so assumptions have to be made between 867 and 1066.
Britannia has the mechanical shift from tribal viking or Ireland to feudal, as well as the heart of the Anglosphere and Tutorial island.
France has Hæstinn to adventure outside, else it's the prime feudal/crusading experience, right there along England.
Scandinavia is that tribal to feudal shift again, but more directly.
Byzantium had primogeniture and is the favorite of Romaboos.
Spain has a Struggle between Feudal and Clan polities.
What regions are excluded here and what mechanical variations do they offer that can't already be used above?
Different starting positions give a fine setting, and that's something that can be enjoyed if you have a love for a region/family/character, but, across the wider community, would require some uniqueness to stand out to show what you love.
Give West Africa a "Munsa" government type and East Africa as "Negus" government, instead of the same wrote Feudal system. Give them a couple of different mechanics for vassal management, MAA/levies, and the African weather patterns, and then save the finer detailing and complications for its focused DLC. India can have a mix between feudal and what the Mandala system will get (heck, use the time between All under Heaven as a testing ground), while Tibet is Monastic Feudal with some different Buddhist mechanics around the Karma tied to ownership "Temple Complexes" that can be upgraded in various forms like Estates, with fights over followers to the most prestigious monastery (within your own realm and externally). I dont want to call them mini-games, but at least something fairly interactable on top/on the side of regular gameplay.
But, importantly, a clan should be a clan, a feudal a feudal, etc. For the fear of repeating mechanics, which does save on dev time but makes things blend together, there should be exclusive mechanics between governments that make them unique, whether its a mana type like Influence that's paired with Schemes, different types of landless buildings, various economic or military structures, something that gives different spins across the world.
My Suggestion for modular implementation is still in progress, but it will, one day, be completed to be ignored on that forum
