1. What you call the ne littéraire (i.e. a standalone ne with a negative value) is not just literary but standard written (and sometimes spoken) French, although limited to set expressions or some specific verbs.

   e.g.

   Ils ne peuvent accepter, si je ne m’abuse.

   Il n‘est pire sourd que celui qui ne veut entendre.

2. You didn’t see ne point because it is very outdated, outside regional spoken French.

3. The ne explétif (i.e. a standalone ne with no negative value) is common in written French and can also be heard in non colloquial spoken French. You need to understand its usage not to confuse it with a negation.

See also:

Why is the "pas" missing?

"Il n'est" without "pas": ne littéraire?

Quelle est la fonction du "ne" quand il est tout seul?

1/

• “Ne…. point” is used the normal way.

“pas” is not the only negative-meaning 2nd particle, there’s also “point” (old or formal), “jamais”, “goutte” (very old), “mie” (very old), “personne”, “guère” (old or formal), “plus”,etc…

There are all constructed on this model:

ne….pas/jamais

etc…

For “aucun”, “rien”, “plus de..” (not meaning “more” here!), it’s the same thing ne… rien, but the construction is a bit different (it’s the only difference).

Je ne vois rien (rien = adverb).
Je n’ai plus de papier. Je n’ai aucun papier) = used as indefinite articles.

You can see that the negation requires always the “ne”, but the 2nd negative particle can have different grammatical natures.

But they have in common: it’s always the “ne…negative particle”.
The dual-made negation.

So, when you have ne… pas, or ne…point, it’s exactly the same.
They are both the 2nd negative particle, have the same meaning
(With this only difference: “point” is stronger, older-sounding and more formal, than the ‘simple’ and common “pas”)
And they have the same grammatical nature. Both are used as negative adverbs.

They are interchangeable (if you ignore the difference in intensity).

We see it rarely, for the reason I mentioned. You can find it often in poetry, or even in novels, when the writer or the character wants to express a “strong no”, in a very formal (and old-fashioned) way).

It’s still used in modern French.

2/ There’s no “ne littéraire”, maybe you mean the “ne explétif”.

3/

You cannot express a negation without “pas”, or one of its equivalents I gave above.
(at least in modern French).

“ne” is also used with “que”, but it’s not a negation.

Je ne fais que jouer.

Something like “je ne joue” could be said in some context in old French, but not in the modern language. So forget the negation without the 2nd negative part.

4/ “ne” explétif.

As I said, “ne” is always mandatory in French, the only case where it’s not, it’s when you talk orally, it’s accepted to skip the “ne” because it’s spoken French, but it doesn’t make it grammatically correct. It’s only tolerated, in some contexts, because people talk fast.

When you write, it’s tolerated when you want to sound informal. But it doesn’t make it grammatically correct.

So, to describe the “ne” explétif, it’s a “ne” that you add when it’s not a negation.
So, it has nothing to do with the theme of your topic “negations”.

It’s used with verb express a fear, a doubt.

It has zero negative meaning.

Je crains que tu ne sois en retard.
J’ai peur qu’il ne soit trop tard.

The “ne” explétif is always used in modern French.

It’s very often skipped in the modern language, but it’s not recommended.