In the matter of the Immaculate Conception, I cannot agree with your statement that by protecting His mother from original sin our Lord belittled His cross. Is not God omnipotent and free to love His own mother above all others?
The wage of sin is death. The Holy Scriptures tells us "But of the tree of the knowledge of good and evil you shall not eat, for in the day that you eat of it you shall surely die" (Gen 2:17). St. Athanasius explains that when Adam and Eve sinned 'They came under the law of death and could no longer live in paradise, but outside of it, to remain in a state of death and corruption.' Since God is just, He is the Father of Truth, He would not go back upon His word regarding death. However, God in His ultimate mercy had no choice but to send His Only Begotten Son to save us. The Son incarnated and became man, surrendering His body to the curse of death in place of ALL, offering it to the Father. We believe that this is the ONLY way for salvation. You can read in detail about this issue in St. Athanasius book "On the Incarnation" www.ccel.org/a/athanasius/incarnation/0content.html.
Because of His ultimate justice, God would not make ANY exception; otherwise He would be breaching His justice. If there was another way for salvation while keeping justice and truth, why go through all this predicament and hassle. Was this all a show?