RCS pointed out that God chose Jacob, not Esau. To me, that is an example of many other "why" and "why not" questions that we could ask our Lord. But to me, this is more an example of the sovereignty of God in relation to one becoming this and another becoming that. After all, we can't all be Esther or Joseph. We can't all be called like Samson or Moses were, but we are all called to be His elected saved ones. I believe even Pharoah could have been saved, if he had chosen it. However, once he hardened his heart a number of times, God turned him over to his evil, carnal thinking.
I think you're on the right track. Esau's and Pharoah's salvation isn't even dealt with in Romans 9. The "it" of "it's not of him who wills or runs" isn't an individual’s personal salvation. The “it” is “God’s purpose according to election”. The context is the issue of national Israel’s role in history (chapters 9-11).
No one has ever been predestined to salvation. Believers have been predestined to conformity to the image of His Son and to the adoption of sons (Rom. 8:29,30; Eph. 1:5,11).
People who have been chosen unto salvation aren’t “unconditionally” chosen.
When people say to "accept" Christ it's usually used synonymously with "receive". But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name. John 1:11 So it is scriptural to say that.