I have a yellow gold wedding set (over 40 yrs), but I do wear mostly silver jewelry now. I do actually mix them. I have several earrings that are both yellow gold and silver. I have seen many halo styles that you mentioned and mostly see white gold. If I were to re set my ring, I would go with white gold (platinum). Also, I think they can use the yellow gold in your current setting or at least buy it from you. Good luck! You're going to love your new ring setting!!