[Mithalwen]

All this is true, but if you want to keep things simpler, the off spring of "mixed" marriages seem to be counted among the father's race (I don't like this as a feminist but it ssems to be the case) although they may maintain ties with their mother's people. So Finarfn and Fingolfin are counted among the Noldor despite their Vanya mother, as are Galadriel and her siblings despite being by blood only a quarter Noldorin. But this is observation not "fact"