Would it be right for any Judge to wave a hand and say, "Yes you are guilty of all those crimes but I'm just going to provide you with a free pardon. I expect you to
be so grateful, you will then be a reformed character who will start to do good instead of doing evil" ?
Yes. But only if you add the condition that the victims of the crimes be suitably compensated.
For the Israelites, justice generally meant compensating the victim, not being punished in the modern sense of the word.
Israel had no jails or prisons.
When someone caused loss to some other person, they were expected to repay the value of that loss.
If they couldn't afford it, they sold themselves as bondsmen in order to raise the money.
They effectively became slaves for a month or a year or whatever it took to repay the debt.
People quickly and effectively learned to follow the rules.
Not because they were afraid of jail or torture, but because they learned the true cost of their actions.
(Our modern justice systems seem to have almost completely lost this concept of reform and rehabilitation.
Punishment and suffering are what the public seems to want and get.)
But that system was for the physical nation of Israel, where breaking the law, sinning, meant causing harm or loss to other people, where compensating the victim literally cancelled the original damage.
For Christians though, sins are crimes against God.
It is not possible for a mortal human to compensate God for what one has done.
The cost of sin is death, and there is nothing one can do to pay that penalty other than by losing one's life.
To think that one can "do penance", or personally suffer pain, or do anything at all to compensate God is blasphemous.
Such ideas make a joke of Jesus's sacrifice.
God doesn't want people to suffer, he wants them to understand, to improve their characters, to repent of their behaviour.
God's grace and forgiveness is a gift, but it must first be deserved and wanted.
No one can earn salvation, but one can choose to remain unworthy to receive it.
God's judgement isn't "fair".
If it were truly fair, everyone would die and no one would be saved.
When sinning against God, there is no such thing as a small sin or a large sin.
One either sins or one doesn't.
One either repents of their sin or they don't.
It's that simple.
What about justice? Is God not just?
2 Peter 2:9 talks about punishment at the day of judgement:
then the Lord knows how to deliver the godly out of temptations and to reserve the unjust under punishment for the day of judgment,
In secular trials, first there is a judgement as to guilt, and then there is a judgement as to degree of punishment.
But that is not how God's judgement works.
God won't torture the "bad, but not that bad" sinners for a few thousand years until they've suffered enough to "purge" their sins.
One either repents of sin and asks God for forgiveness or one doesn't.
There is no middle ground.
One either receives salvation or one doesn't.
Will God torture the unrepentant for all eternity?
Will the unrepentant receive an everlasting life of torment?
Rather than repeating the verse mindlessly, read what John 3:16 actually says about this:
For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life.
The saved will receive "everlasting life", and the rest will "perish".
There's no third alternative, no compromise; it's either everything or nothing.
God is a god of love, who "desires all men to be saved and to come to the knowledge of the truth".
People that think of God as sadistic or vindictive are confusing him with Satan and worshiping the wrong god.
Those that reject his salvation will not have to suffer torture for all eternity; they will simply be destroyed.
The word in 2 Peter 2:9 translated as "punishment" is "κολαζομένους" G2849 - kolazō - Strong's Greek Lexicon.
Its primary meaning is "properly, to lop, prune, as trees, wings.".
Those that reject God's salvation will be pruned away like the useless parts of a productive plant.
As Matthew 3:12 says in another agricultural metaphor, God will "gather His wheat into the barn; but He will burn up the chaff with unquenchable fire".
No one deserves salvation more than anyone else.
In fact, no one "deserves" salvation at all; it can't be earned but is freely given to those that want it.
Permanent death and destruction is God's punishment for the unsaved.
Everlasting life and blessings are God's gift (not reward) for those that truly want it.
That is the justice of a loving God.