I think OP has it pretty down. I come from a high school that's 2/3 Asian. Mostly Chinese, Indian, Japanese, Korean. The Vietnamese, Filipino population is very tiny here. Only 1 black kid in the whole high school.
We were the nerd school. Top public school in the Bay Area. It's very different. Most parents came to the US not just for a better life but came for grad school. Many of them work in the tech industry, and household incomes are 200k+ We study our asses off and feed the Ivy leagues and top tiered public UC systems (i.e. Cal and UCLA).
I go 20 min away to my gf's neighborhood and it's all Vietnamese. The crowd is 100x different. People came to the US to escape from the war. Many lack education and work blue collar jobs. Their kids are using this as their first opportunity to do well for their family. Compare that to me and my friends. The kids are made sure we don't screw up because our parents all came from the top schools overseas and we're meant to not screw up their awesome legacy.
Also it's important to break down Chinese and Taiwanese. Before 2000, many of the smart Chinese people you saw here were either from Hong Kong or Taiwan. Since then the mainland population coming to the US is growing. If you drive down the Chinese infested cities like Rowland Heights, Diamond Bar, they're mostly Taiwanese/Cantonese. This is changing though as China grows in wealth.
Anyway, so my gf comes from a school primarily Vietnamese and Filipino. Very different. Ghetto. Drugs, fights all the time. When our school makes the news it's about people hacking into the school database to change grades. When her school makes the news its about some student getting shot by a gang at a local park. Yeah. Different world.
I've heard from a few Chinese/ Japanese that Koreans were considered to be at the bottom of the pile - largely stereotyped to be dumb uneducated farmers up until very recently. Even though they may now somewhat respect their socioeconomic progress, I think many of them still believe Koreans to be inferior.
Maybe in Asia, but Korea has developed very well in the past two three decades. The ones in the US that I know come from families where their moms wear the pants in the marriage. They beat their kids to study harder, etc etc. Yeah. They're hardcore. Oh and Christian too.
Going to college transformed me. While college was still 50%+ Asian, there were a lot of underprivileged kids. I did Engineering, so I was still with the nerdy Chinese/Japanese/Korean kids I grew up with at home, but there's a lot more "ghetto" types around the school. There's a lot more kids who just have more freedom rather than the ones like me who have parents breathing down their necks going "You're going to med school/biz school/pharm school/engineering phd and get a 4.0 GPA" and there's a difference. The ones who drift around are the ones who get out of school learning nothing, having taken idiotic classes. Most of my friends went straight to grad/professional school or landed a nice job at a Fortune 500 company. The business/econ ones went straight into I-Banking or accounting, and I know several of them at the Big 4.
Unfortunately some of the way Asian kids are raised with their parents nagging them left and right can produce socially awkward kids (READ: SKIM MILK and FBB). I guess it woudl work in Asia, but when you have a kid who's told to study their asses off and then integrate into the American culture, they get confused, and they get kinda lost.