How come you did not include vs 17-20? especially vs 19, "It pleased the Father than in Him all the fullness should dwell, and by Him to reeconcile ALL THINGS to Himself, by Him, whether things on earth or things in heaven..." He DID NOT RECONCILE BELIEVERS. He reconciled all things. This is the Incarnation. as is I Cor 15:20-22, II Cor 15:18-19, II Tim 1:10. I John 2:2, Heb 1:9, 14-16. Rom 18-20. There is no mention of believers being saved, converted, in any of these texts.
Next, you misunderstand the fall as well. The world was NOT created for a redemptive purpose. The redemption plan was foreordained because God knew Adam would sin, thus totally destroyed the purpose of God creating man, to have union with Him
God did not desire that Adam sin or cause him to sin. Foreknowledge or foreordination does not mean God needs to actually do something in order to know.
He wanted to have union with man for an eternity. For this reason He needed to overcome death and also to provide a sacrifice for sin. Overcome death happens in the eschaton when death will be defeated finally, in the meantime man has been appointed to die once, so that sin will end in that mortal flesh.
The sacrifice for sin would enable God to have union with man in this life, if they believe. When one repents, he will be forgiven his past sins. For future sins, continued confession will be necessary in order for man to remain in union with God.
Christ did not make, force, convert, anyone to belief from the Cross-death/resurrection or at any other time. It becomes a free choice of man whether he will believe or not, or even if he does, but later rejects Christ. Man is free and will get his just reward.
I don't think you understand this text or the context because it does not say what you think it say regarding your view. First, your idea that the redemptive plan was God's purpose in creating man is incorrect. He created man to have union and communion with man. Man was given everything in creation to use and give back to God in thanks and adoration. Man was purposed to attain to immortality if he remained obedient to God. However man failed, God knew he would fail for which He planned a redemption for all that God had created would be given to His Son to reconcile the world, all men back to God.
Why, so God could again be in union and communion with man, Christ became the second Adam and corrected the first Adam.
Before all times. But how does that help your view. It says nothing about Christ redeeming some as believers. The redemptive plan, as explained above, was to correct what Adam did, which is clearly stated in I Cor 15:20-22. Do you think that God had an ongoing plan for His creation or He knew what His plan was and executed it on foreknowledge? I'm also not sure you understand "foreknowledge either,. You seemingly think God needs to do something in order to know.
You don't indicate by your statements that you understand the Creation of man, that man fell and the whole creation was condemned to death. Because you don't really understand these, one would expect you would not understand the redemptive plan either.