Do you know what ultimate power is? It isn't the ability to do whatever it is you want, rather it is the ability to accomplish whatever you set out to do without fail. This is the Omnipotence of our God, that his will is sovereign over all other wills, powers, and principalities. That is to say, ultimately all wills are made to accomplish God's will.
When God sets out to create for himself mankind in his image, he does so knowing of our inevitable rebellion. And still he creates us because he is sovereign, because he knew he could do it. He sent his Son as the express means by which his will would be fulfilled in the world, that namely fully free human beings would come to love their creator God, that from them he would get Glory for himself through his awesome works. Creation and the fall were just the beginning of God's plan to create for himself a kingdom of believers.
God has promised salvation to all those who love him and has given us his spirit as a deposit and guarantee of what is to come. It is not our place to question how God chooses to act. Can the clay criticize the potter? We don’t always know how God accomplishes his will but we can be assured of this: As surely as the LORD lives, He will do it.