It's interesting to me that what is rarely brought up in these threads is that with the exception of southern blacks in the black belt, most ethnic minorities are heavily concentrated in cities, where democratic machines are very efficient at mobilizing and reaching voters.
What if this Asian transformation is in reality a symptom of the growing urban-rural divide?
There are a lot of rural Hispanics. I don't think they vote that differently from suburban Hispanics.
Republicans who think the right candidate will get them Asian or Hispanic voters are over-optimistic. Most minorities vote Democrat for a simple reason: they hold socially and economically liberal beliefs. That can be changed, but not in the short-term.
Asians and Hispanics aren't going in the same direction though. 2nd-generation Hispanics (excluding Cubans) are typically more conservative than their parents as they assimilate. Meanwhile, Asian voters go in the opposite direction because they probably cannot be assimilated in the same way and start adopting views similar to those of the racial "other" in American society (blacks).
A GOP that gets 60% of non-hispanic whites, 35% of hispanics, 15% of Asians, and 15% of blacks is in a perfectly fine position.