Preaching the Gospel, Preparing a People
A good scripture to consider is Romans 5:8 "God shows his love for us in that while we were still sinners, Christ died for us." This shows our Creator has the capacity to love people who have sin in their lives.
The purpose of His love towards sinners is to rescue us from our sins so we might have life everlasting. However, some people will refuse to be rescued and will stubbornly persist in sin even after being enlightened. Such people will not receive life everlasting. Even this act of denying everlasting life to such people is an act of love and mercy on the part of our God. He does not force people to live forever if they choose the way of death.
A helpful bible study would be to investigate what the bible teaches about God's love. I recommend the free bible study guide on this site: https://www.ucg.org/bible-study-tools/booklets/the-ten-commandments/a-royal-law-of-love
You have it about right I think. Rather than memorializing significant events in Jesus' life the sequence of the 7 holy days go through God's plan for the salvation of mankind step by step. That path of salvation begins with Passover. Jesus Christ Figures prominently in each of those steps. Here is an interesting article that elaborates on this concept and sheds light on all the holy day observances and how they fit together - https://www.ucg.org/beyond-today/beyond-today-magazine/gods-feast-steps-of-salvation
What make you say our bibles are corrupted? Are you referring to intentional mis-translations or are you referring to the notion that the word of God can only be understood in its original language [i.e. Hebrew]?