I think you have entirely the wrong view and concept of God's purpose in giving the law. The simple truth is that anyone who obeyed the law perfectly as Jesus did would have eternal life and would have no need of the justification and regeneration made available through Jesus Christ's sacrifice on the cross. Without doubt that is how God would have us live. That is how one would be perfect as your Father is perfect. But as Paul stated, none have ever done so, and hence the need for salvation by the grace of God through faith in Him.
As should be obvious, so much of the NT actually repeats all of the moral character of the law.
Rom 8:1 There is therefore now no condemnation for those who are in Christ Jesus. 2 For the law of the Spirit of life has set you free in Christ Jesus from the law of sin and death. 3 For God has done what the law, weakened by the flesh, could not do. By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh, 4 in order that the righteous requirement of the law might be fulfilled in us, who walk not according to the flesh but according to the Spirit.
The weakness in the law was not due to the law, but due to man's failures. According to Romans 8:2 above, the law was weakened by man's flesh.