I wouldn't say that Cap + a WOC would be hip, exactly, as multiracial families are not a subject that discussed nowadays, but it would be a bold decision, as, for some reason, it still seems to be taboo for many people, especially with the symbolic importance that having Captain America involved in such a story would have. I do think it's a pity that, except for Luke Cage/Jessica Jones, multiracial couples don't last long in the Marvel U, with Storm/Wolverine being the latest example of that.