I think Cathay has very generic and boring lore that doesn't fit the classic grim fantasy inspired by history that warhammer used to be. Here are some changes I came up with while taking a shit.
>no dragon children or emperor's, there's just ONE dragon that lives in heaven at the top of some cloudy mountain top that the yellow river flows from
>this dragon is extremely powerful and rules the heavens, controlling the weather and essentially all life in Cathay
>this dragon, heaven, is obsessed with his notion of balance and give heaven's mandate to whatever ruler manages to claim top dog
>the Cathayan emperors will rule with heaven's mandate which means good weather, harvests and the yellow river flows calmly
>in order to keep ruling with heaven's mandate they must ensure the people worship the dragon, spirits and the ancestors, some version of Confucianism and whatever big projects the dragon demands
>so if the emperor fails to ensure the people behave, level a mountain to ensure sunlight reaches a tree for balance™ and defend Cathayan values he loses the mandate and disasters strike Cathay
>plagues, famine and natural disasters etc
>this continues until the current dynasty is toppled and replaced
>the dragon is uninterested in the outside world and views Cathay as his own little garden, hindering technological advancement or societal progress that doesn't fit his "balance"
>all of Cathay is surrounded by a great wall to keep out anything that can disrupt his garden
>however chaos exists inside through cults and beastmen while a monkey man leads a popular uprising in the shadows against the mandate of heaven
>Cathay in the old world would be based on the Ming with a strong focus on gunpowder weaponry together with heavily armed cavalry
>fuck dynasty warriors and look at the brigantine armors used by the Ming
>gameplay would be focused on elite cavalry and rifle infantry with additions of terracotta warriors and monk warriors inspired by the classics