The HDI chart is in this article, and still has no correlation:
The Magic Gun Evaporation Fairy
Three Reasons Why Gun Ownership Rates From Other Countries Don’t Matter
The suicide issue is unpacked in depth in this article:
The Left Is Making the Wrong Case on Gun Deaths. Here’s a Better Case.
The gun conversation in this country has real, systemic problems.
Your third point doesn’t make sense. If an effect is there, it should be there, at least at a multivariate level.
I don’t object to legislation changes, but the changes need to be made based on reality, not freakoutery and emotion.