Well, the sin is against God, and someone has to carry out the punishment ("pay the wages"). Who else would do it if not God? Plus, this is clearly how the text of the OT portrays it. God took lives, a lot of them.
Is God’s justice death?
Sometimes, yes. Jesus also demonstrated God's justice, such as with the adulterous woman, so it isn't always about death.
Why isn’t this concept the parent of atheism?
I don't know why it would be. An all powerful God creates His creatures and they are His to do with as He pleases. Fortunately, He decided to save some, and all who come to Him will be saved. At the same time the wicked will be judged for their sins and forever separated from God. I don't see how any of this would lead to atheism.
FK: “To eliminate the God who metes our justice is to eliminate the God revealed to us in the OT. I don’t see that as a good option. :)”
I’ll grant you that it will eliminate a Western misconception of the God revealed to us in the OT. Personally, I see that as a good thing. :)
So, do I take it that you don't think God did all those things the text says He did in the OT?
That's what the West says; its the result of mistranslating the NT Greek word for sin, "αμαρτια", which means "to miss the mark", the mark being Christ.
"and someone has to carry out the punishment ("pay the wages")."
Well, that's certainly consistent with the idea that God's offended dignity could only be assuaged by the bloody killing of His Son. Why does "someone", other than the sinner have to carry out the punishment. Why isn't it simply the inevitable result of sin?
"Man's transgression against the Creator's righteousness brought the soul's death sentence into effect; for when our forefathers forsook God and chose to do their own will, He abandoned them, not subjecting them to constraint. And for the reasons we have stated above, God lovingly forewarned them of this sentence. But he forbore and delayed in executing the sentence of death upon the body; and while He pronounced it, He relegated its fruition to the future in the abyss of His wisdom and the superabundance of His love for man. He did not say to Adam: 'return to whence thou wast taken,' but 'earth thou art, and unto earth thou shalt return' (Gen. 3:19). Those who hear this with understanding can also comprehend from these words that God 'did not make death' (Wisdom 1:13), either the soul's or the body's. For when He first gave the command, He did not say: 'in whatsoever day ye shall eat of it, die!,' but 'In whatsoever day ye shall eat of it, ye shall surely die' (Gen. 2:17). Nor did He afterwards say: 'return now unto earth,' but "Thou shalt return' (Gen. 3:19), in his manner forewarning, justly permitting and not obstructing what should come to pass." +Gregory Palamas, Physical Theological Moral and Practical Chapters
Tell me FK, when the tsunamis killed so many people out in the Indian Ocean, was that God punishing sin, just some random and tragic event or finally the result of sin's distortion of the natural order which God allows?
"So, do I take it that you don't think God did all those things the text says He did in the OT?"
I believe He did all sorts of things in the OT. I also think that He allowed other things to happen out of mercy because death can curb sin; I also think he sorrowed at other things and I firmly believe that, "Very often many things are said by the Holy Scriptures and in it many names are used not in a literal sense... those who have a mind understand this" +Isaac the Syrian, Homily 83 and "It is because fear edifies simpler people," +Basil the Great, That God is not the Cause of Evil.