Have you ever known someone who sparked the thought, if that guy knew someone just like himself, he'd hate him? Have you ever wished that that person would have to meet his spiritual doppelganger?
A truly just world would be one in which different personality types could only associate with others like themselves. All sociopaths would have to live in a community composed exclusively of sociopaths. All of these con men would find it near impossible to con or even manipulate each other, since they would all be onto each other's tricks. And that would be exactly what they deserve.
For all those affect hungry sociopaths who feed off others' affections (while offering only the ersatz variety themselves), they would get only the hollow claims of affection from others. And sociopaths -- those famously disloyal and hateful creatures -- would get only disloyalty and hate from everyone they came into contact with. Which is exactly what they deserve.
That would be justice.
Garden variety narcissists would have to live on an island populated only with other narcissists. None of them would ever admit they were wrong, and all of them would only want to talk about themselves. But nobody else would ever admit fault, either, and nobody would want to listen to them talk. Everybody would demand his own way, and nobody would acquiesce willingly.
People with Aspergers could live in a community with other Aspies. Each would rigidly demand his own way, deny to each other what they had just said, put words in each other's mouths, and only talk at, not with, each other. And they would all have to suffer through each other's melt downs.
And so on, for every personality type. This would be a world where everyone got exactly whom they deserved for company.
Frankly, I wouldn't even mind a world where people were segregated by IQ. (This would be similar to, but far more effective than, our current college system.) Smart people wouldn't have to put up with dumb people, and dumb people wouldn't have to be looked down upon. And everybody would be able to relate to each other much better.
And if, say by accident, someone were to nuke the Island of the Sociopaths, well, I wouldn't shed a tear.