Here's my view on these characters:

tortured soul to gain recognition after death. The curse of a busy mind, I suppose.

not the curse of a busy mind: the blessing of being highly sensitive; the curse of being unable to detach from the emotions that flood them constantly, because of it.

A profound influence on modern thought, a towering philosophical thinker, and yet, a very sad man living a very sad life.

in German we have the word 'grübeln' = to get stuck in your own thoughts, or more modern maybe: 'to cook over something for too long'.

being highly sensitive, while being too attached to their feelings they are under so much stress, that some people go too deep into their thoughts to compensate.
this can lead to such great works, but at what cost and to what end, really?

It's no wonder his lament that God is Dead is one of his most lasting philosophical outlooks on life.

It's no wonder that shit happened to him, maybe he should have studied Goethe's 'Faust' or the story of Babylon or something, or Greek tragedies.
It's like the oldest story, ever...

Is eternal legacy really worth it?

It's not worth your soul... if you believe in such things :D