Complicated questions you raise. There is more interracial dating, and interracial attraction, than interracial marriage. Marriage being about much more than attraction, if the partners are being smart about it. Obviously, American-born Asian women are “whiter” culturally than immigrant Asian women, on the whole. I unfortunately have no experience dating American-born Asian ladies, only immigrant Asians. But I think both groups seem equally feminine — which is not to say that all the ladies in either Asian group are. Generally, I’d say American-born Asian ladies are somewhat, or even, better-looking.
Having traveled extensively through half-a-dozen countries in East Asia, I'd have to disagree. However, to each his own.