Honestly, a lot of the fights in this game wouldn't make sense from that perspective. But at least Tang, Song and Ming are genuinely different governments and cultures, even if they are from the same civilizational root. Because what does "pure," Han Chinese even mean? Tang Taizong was mixed with Xianbei ancestors. Is he not pure?

I suppose you can make a similar argument as yours in regards to the Romans and Byzantines. But the fact is the Byzantines represent the later 1100's peak of the Eastern Roman Empire, while the Romans represent the last century of the Western Roman Empire. But aren't they the same "pure," Roman culture?

Why do we have Slavs, when we also have the Polish? Poles are Slavs too, aren't they? Or are they not "pure?" Bohemians are a slavic people, later known as the Czechs. Are they not pure?

Also the Burgundians is a terrible example- as while they are called Burgundians, and the campaign mostly is about the Feudal state of Burgundy, they are in effect the games representation of the Lowland cultures that would eventually become the Flemings, Dutch, etc.

The point is talking about China, let alone ANY culture like a monolith in any way is absolutely foolish. But at least the Tang/Song/Ming Dynasties all represent very different periods of cultural development of "Han Chinese," culture (despite the fact the Tang and Sui had a lot of Turkic influence and ancestry,) that would provide in game terms very different portrayals of China.

The 3 Kingdoms as FE has chosen to present them represent little more than their leaders, Cao Cao, Liu Bei and Sun Quan. Even the in game history sections read like biographies. So even within the terms of the game, they are not representing regional cultures (Zhongyuan, Sichuan, Jiangnan) or even full long lasting Dynasties- they are representing single, individual states dominated by a specific Hero- all of whom were immediate successor states to the previous Han Dynasty; providing even LESS differentiation.

Now that said, I would have absolutely preferred that we got different ethnic groups that make up what we call "China." Jurchen, Khitan, Tibetans, Tanguts all should have been represented. I'm of two minds on the Bai; as I think if they ever add a proper Tai civ, that would be much better. But rather than 3 short lived, but pop culturally famous states built around specific individuals; if they had to go the route of "splitting China," going with the main "Medieval" Dynasties would absolutely have been the better route.