You are "too this" or "too that" will happen. It just will. You will stumble onto it. The orthodoxy, whether that is traditionalist Chinese people or conservative Westerners, or literally Orthodox Jews in Williamsburg, can't help themselves on the subject of identity.
One of my favorite expressions is "to cast aspersions." And cast those buggers people will. Being mixed is hard for them to grapple with. And for whatever reason, they will act as "cultural reactionaries," telling you that despite identifiable partial 'such and such' heritage, you can't truly be 'such and such' ethnic and/or cultural identity.
There is no insta-fix to pleasing everyone all the time. What I'm hoping for though is the psychological stability to deal with these "aspersions" shocks. That is to absorb them, move on, and make sure that in no way will someone’s kneejerk “you are not this, you are not that” absurd identity ceiling, self-decreed upon you, impede in any way your ability to make meaning with your identity.
Not every old curmudgeon needs an attitude adjustment... Not every grump needs a lesson in social justice...