You were doing so good until....CALVINISM. This is NOT what Romans 9 is about. It's about God choosing to save GENTILES over Israel as a nation. The older brother in the case of Ismael and Isaac, and Jacob and Esau represent Israel. Pharaoh represents Israel. The whole point is that God hardened or blinded Israel so that salvation could go to the nations. Calvinism has blinded you to the truth.