Cuban-Americans whom Trump courted with anti-Castro rhetoric.
First of all, Cuban-Americans are going to have the black-white split that ensures that they will be treated differently in economic opportunities. More recent Cuban Americans are less "white" than those who fled Castro early.
Second, Cuban-Americans are getting better educated, which ensures assimilation into other groups of well-educated people. Unless the GOP quickly abandons its anti-intellectual demagoguery, educated Cuban-Americans who have more stake in the American future than the Cuban future are going to drift D. This may include Afro-Cubans in America.
Yeah, ironically Cubans are the most likely to trend D. Because in addition to the specific factors you mention, the fact that they swung R means there is more potential ground that can be made up than with other groups.