If they are incorporated into his plan, then he has ordained everything that occurs. IOW your sins are as much a part of God's plan as your salvation. One man's salvation is part of God's plan and another man's damnation is equally a part of God's plan. I suspect you recoil at that fact.
Is God passive in all this? Does he hold our will inviolate? Did you make yourself willing to come to Christ, or did God by his mercy and grace make you willing? If He made you willing then you cannot claim it was YOUR free will that brought you to Christ, but God's will.
Those doggone calvinists in the tradition of arminius are absolutely on target! :>)
{!}