It is , indeed, a psychologists' and sociologists' dream to do research in China.
There is only one country that I can compare China's net internal migration with -- in breadth and expanse -- and that is the United States. The criss cross of Westerners moving to the East Coast, Southerners to the Midwest, or Northern to Midwest, South or West to midwest --- is just amazing.
For example, we have one American member
@SvenSvensonov who's from Utah (i think if my memory serves me right) and now he's in Virginia. For me my port of entry to the US was in California, then now I'm here in New Jersey (east coast). My gf (she's Italian-American), her family originally came to the US through New York City back in the early 1920s, but now they're here in New Jersey, tho she has a lot of relatives in Chicago (Midwest), and also in Florida (South).
So yes, seems like Chinese net migration from north to south, south to north, east to west, west to east, central to east, central to west, south to central etc etc --- is similar to US. Its good because like you said there is a cultural dynamic here. I can only imagine what this means in terms of food and cuisine adaptations, local language, religion practice, family raising patterns et al !
Hahahaha you are new, in time, you will know what i'm talking about.