Concerning "1. My ethnicity should match my family tree", it's my sense that the reason one's genetic ethnicity might not match one's family tree is because of the random aspect of genetic contributions of a parent to their child. Fifty percent of the child's genetics come from the mother and 50% from the father, however, there's no guarantee that grandmothers are contributing 25% and grandfather's 25%. It's possible that the grandmother gets the full 50% contribution. It's a random thing. So, if grandma gets the lucky draw and contributes the full 50%, then grandpa gets nothing and his ethnicity is lost in the grandchild. Am I right or am I right? You can tell me I'm wrong. I'll learn from it.