My understanding is that God created Adam and Eve from scratch with free will and He could foresee that they would sin. If that premise is true, why would God not have scrapped that design and tried another and another until, with His ability to foresee, He came up with human creations that would not sin (still exercising their free will)?
I’m not sure if that particular concept would be totally congruous or compatible with the fact that free will - in order to be free will, must be absolute. We even see in the angelic nature , those who never sinned (or
would not sin) and those who did - even though in their case the choice (of to serve God or not) was one definitive irrevocable choice with eternal consequences. Shall we also ask God to change the Angelic um, (your word - not mine)
design ?
God is humble. In His plan to redeem mankind He decided it would only be necessary to create
one human being free from all stain of sin and who
would not sin . . . the Blessed Virgin Mary. Though awkwardly worded, the idea you mention of “another design” is, in one sense, not totally foreign, since Our Blessed Mother - the Virgin Mary, is referred to as the
new Eve ; but even
she had to be saved.
In your concept of “scrapping that design”, how would you propose that God deal with the salvation of Adam and Eve ? IOW how would the debt be paid ? We need to remember that death entered the world through the devil’s envy as well - not only through our first parents’ sin.
God has indeed already
scrapped that design in redeeming us: But rather than destroying or discarding us as an old model or prototype, we are now raised higher than we ever were before the Fall - thanks to our Blessed Lord Jesus Christ. Each one of us, in Christ, now receives a lofty calling.
Catechism of the Catholic Church; The Fall