Why Require the Sacrifice of Jesus?

I've given considerable background thought to this question. I've read more than a few things on this subject, and I think I could do a fair job summarizing the essential points of the doctrine (see below). But as I pondered this, I kept coming 'round to a more basic question:

Coming from a perfect God, is the answer "Just because" sufficient?

Our understanding of God, as recorded in the Bible and built upon by two thousand years of doctrinal development, still admits to grand mysteries that will never be understood. One of those mysteries is the true nature of the Trinity. Another is exactly what transpired at that moment when Christ bore our sins and served as an atoning sacrifice.

One of the things I have discovered about myself -- or one of the things God is trying to get me to listen to -- is that I do not and will not make a good Christian apologist. I do not relish a debate ... particularly on this general topic. Because ultimately it is a subject that cannot be argued conclusively. Ultimately the logical basis for the entire Christian faith is rooted in the Bible. All one need do is reject the basic premise of the Bible's authority on the subject and any further attempt to argue for the Faith is, truth be told, essentially futile.

Note: or, more precisely, it would require that the apologist cycle back, time and again, to the question of God's revelation -- general as seen in nature (though even that is frequently rejected by those wishing to deny a creator God); specific as found in Scripture. The basic point here is that the Christian argument cannot be moved forward without settling on this basic premise. It is like me trying to construct a geometric proof when we can't even agree on what "parallel" means ... and by that I mean in the Euclidean sense, not some weirdo black-hole, gravity-warped, time-compressed, string-theory, King's-pawn-gambit world where parallel lines do in fact cross multiple times. :-)

* * *
Now, all that said, here's what I believe is the common explanation for the necessity of atoning sacrifice:

• Mankind has committed -- and continues to commit -- a tremendous offense to God. Mankind's sinfulness is not measured in degrees from God's perspective. We are all equally abhorent to God. Absent Christ's righteousness, Mother Theresa was no better than you or me. (I am quite certain she would have agreed with that. What else explains her remarkable humility?)
  
• God is a perfect, as you point out. One aspect of his perfection is his perfect sense of justice. A perfect sense of justice would not -- could not -- simply allow an offense to go unpunished. It would be akin to us watching a hoodlum rough-up a helpless old lady, and then watch as police stand around, laugh and do nothing about it. Our sense of the injustice in that would ignite tremendous fury within us. Magnify that sense of injustice an infinite number of times to approximate God's perfect sense on the matter.
  
• God has ordained that the shedding of blood is what shall make an atonement for the offense committed. (Leviticus 17:11, NIV: "For the life of a creature is in the blood, and I have given it to you to make atonement for yourselves on the altar; it is the blood that makes atonement for one's life.")
• To achieve reconcilation to a perfect God would require a perfect sacrifice. A goat would not achieve lasting atonement -- and indeed it did not; in the Old Testament the day of atonement was an annual event. The sacrifice of a mere man would not for the same reason. It would take the sacrifice of a perfect man. That perfect man is Jesus of Nazareth.
• Hence Jesus as the incarnate God -- God among us; the Word become flesh -- perfect in his obedience to God, utterly sinless, a spotless atoning sacrifice.
  

Notes:

• This does not explain how Christ's sacrifice was an atonement for our sins. That's a mystery.
• This logic is not unassailable. Again, it is constructed upon a critical cornerstone; that is, the authority of the Bible's recounting of this.
  
• This logic is meaningless to anyone who does not accept or comprehend the idea of a perfect God.
• This logic is meaningless to anyone who rejects the notion of our inherent sinfulness.
• This logic is meaningless to anyone who thinks of Jesus as simply a "great teacher."
  
• This logic is meaningless to anyone who rejects the notion of God possessing anger or wrath.
• This logic is meaningless to anyone who longs for a God who simply turns a blind eye and allows us to be captains of our own destiny; to continue in our chosen ways; to demand nothing of us but grant us our every wish.

* * *
May the Lord forgive me if I've done a disservice to His Sovereign Truth. The Bible says (somewhere ... drats! I wish I had more patience to look these things up) that a particular responsibility will fall upon the shoulders of teachers of God's Truth. I do not think I have contradicted Scripture here; but I do not think I've offered a particuarly compelling recounting of it.