I haven't read the entire thread, so excuse me when I say things that maybe have been said before.
There is a certain age, roughly child & teenager, when a person's own moral, ethics and boundaries of acceptable behavior are setting. And basically, those boundaries are transferred from the immediate society around.
This is why anybody, who says harder punishments don't discourage crime, lies. Harder punishments by themselves don't stop anybody from committing a crime. That's unfortunately true. But the persons own moral boundaries do. And these are set by how seriously the society regards those crimes. And that is reflected in punishments. And this is also reflected in our inherited instincts that are in play in our social behavior patterns. We crave to see criminals being punished for what they've done. We want revenge. We do that because it's a social behavior that has been handed down by evolution, because it really works to make the society function.
But that doesn't transfer to that death penalty is a good idea. On the contrary, it gives the message that it's ok to kill someone who has wronged, or is perceived to have wronged. A society that wants life to have a high value, should have harsh punishments for murder, like life sentence, but not capital punishment. I do not know why the Middle East is so prolific in producing nut cases who'll happily primary-target and blow up innocent people, and then expect God to favor and reward them for it. But I think the public, bloody beheadings and stoning of women, that counts as entertainment in these countries, deserve some speculation.
When it comes to minor tolerances and intolerances, it's better to be tolerant and mainly only respond to direct attacks on tolerance. Those should not be tolerated.