Mapwise, at a minimum they would need to include China proper, Korea, and northern Vietnam, and if they went through all that trouble it's hard to see them leaving out Japan. For these Sinosphere countries we're looking at, at minimum, a new religion group and either expanded Imperial government or a new Imperial government type separate from Feudal. Mainland Indochina is maybe not essential, but it would be a pretty straightforward case of adding in cultures and titles, because these states were very Indianized and the existing Buddhist and Hindu mechanics would work reasonably well for them.
Religion-wise, I'm not in favor of separating Confucianism from Daoism. In this game, religion divides up important mechanics, who can and can't intermarry, who is and isn't a valid Holy War or Revocation target, who hates each other- none of these are applicable to Confucians and Daoists (or East Asian Buddhists, for that matter). These should be "schools of thought" like the the Ashari and Mutazili for Sunnis. Millenarian uprisings could make up the heresies for this religious group. Key features would be the schools of thought, polygamy, and lack of Holy War CBs. In exchange for the lack of Holy Wars, they should get fairly strong CBs for use within their own culture groups, similar to the Indian Subjugation CB, to facilitate wars of unification within, say, China or Korea, without giving them powerful tools to expand against different-culture neighbors.
Mechanics-wise, Bureaucratic government would be a major challenge. Delegated appointments, regular promotions and rotations, and the occasional push to make individual titles hereditary (this is what led to the collapse of the Tang shortly after the 769 start date) would all need to be accounted for. This is the single biggest problem for the game and the main reason why I don't think a China expansion will happen. If they can do it, I doubt the AI will be very good at handling an appointment-based government. And the three-holding system that works well for the European nobles-burghers-clergy trifecta doesn't really have a place in the Sinosphere.
Lastly, naming would be a major issue because of few surnames (a lot of them homophonic) against lots of characters. How exactly they could work around that is beyond me.
If there gonna do China or Japan, why not just make Sengoku 2? I almost think they need to focus back on actual Medieval stuff in Europe for the next DLC.
For one, Sengoku was just Crusader Kings with a fraction of the content. There's not much reason to bring it back. Two, it wasn't a large enough success for a new game to really benefit from 'the Sengoku brand.' Three, the Sengoku Jidai was a very short era, so either it'll be a large, expansive game and be mislabeled, or be a Sengoku/March of the Eagles-type game that really doesn't cover any bases for East Asia as a whole.
There's also a bajillion other threads about China. How about you post in one of them instead of making another "China China blah blah blah" thread?
The great thing about threads is you don't have to read them or post in them if you don't care about their topic.
Fun fact: in those threads I've posted that I don't think they will make a China DLC, and probably shouldn't. Either way that decision has already definitely been made by the devs and won't be altered by what we do or don't make threads about. See how I can think that, and still want to have a discussion about a hypothetical?
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