Others might disagree but I'm not sure our differences are salvation issues which is what is important to me . I understand that you will see this differently but your belief seems to squash hope to me. How could I lead someone to Christ and at the same time tell them that they have a (what?) 50%? chance of being accepted. (or rejected?)
If you "lead someone to Christ," that person's name was written by God in the Book of Life from before the foundation of the world. God will have used your witness to be his earthly instrument to bring about His divine plan.
If that person does not come to Christ, it was also God's will, no matter how fervently you preach the Gospel. If God wants someone, what could possibly be strong enough to keep that person from God's grasp?
Squash hope.
To believe that God is in control of all our lives, and that God will not let any of His sheep be lost, and that only God truly knows the wheat from the tares, and that what may look to us like a tare may yet prove to be wheat, if it is God's will, is the most hopeful, egalitarian of beliefs.