My preference is a woman I connect with. Culture might (or might not) have an impact on that, but ancestry won't. We're all descended from the same man ~60K years ago and a woman ~140K years ago. Makes no difference to me what your more recent ancestry is...
No, but being from Kansas I don't have much to choose from...... Certain parts of the world it would be frowned apon, bigtime. But doesn't bother me at all.
I don't really have too much of a preference. I am Native American and when I have kids I would like them to be able to enroll in my tribe, but if not it doesn't matter. My mom gives jokingly gives me a hard time about dating white girls instead of native american girls though. I just tell her to find me one that's good looking and not crazy, and i'll give it a try. No luck so far.
I do have a thing for red heads though, I really do.