So I think I now know what Ni is like when its used.
You're mostly if not entirely wrong when it comes to me as a Ni-dom.
Its seeing the whole picture at all times. Both sides of the same coin. When someone says they are "Strong Willed" that also implies that they are "Stubbornly narrow sighted." If someone says they are "very shy" it also means they are "good at keeping secrets." If someone says they are a psychopath, another may argue they are "willing to do what others are not."
For every bad there is somehow a good. A yin and a yang.
If it's N at all, it seems more Ne to me. Ne sees lots of possibilities. In any case, that example seems more to be about human value judgements, which would be F-related (Fe or Fi).
Ni can shift perspective, but not in the way you're describing. The flavor of where you're coming from here is just really inaccurate, when it comes to my own experience as a Ni-dom.
And when you use Ni, you see all of existence in your mind. Civilizations flowing, coming and going, mountains forming and crumbling, cultures forming and spreading... and in the end the Ni dom (INTJ INFJ) is left feeling small, wondering how its possible to do anything good in such a huge world. (many INFJ's type as enneagram 4 scared of being insignificant, and many INTJs type as 3 or 5, scared of being worthless or inadequate.)
No, not in my case. From Ni perception, I see the parts of existence that I can see from my specific location in the landscape. Not all of the landscape. It's is pretty huge, though.
I find the the part about feeling small and wondering how it's possible to do anything good in such a huge world actually pretty ridiculous when applied to my own experiences and perspective. Being part of something larger isn't a problem for me at all. Not sure about Ni-doms with other enneagram types, but at the very least you're overgeneralizing here based on incorrect initial comprehension IMO.
When I use my Ni I see everyone around me as equal to me, but I also see myself as having some kind of a gift. The ISTJ who acts like a badass and tells everyone how tough she is, does so because she feels no one respects her. So I will give her this respect and as a result she will give me something in return, perhaps she will get along with me or protect me or help me in the future. The ENTJ asks a lot of questions and constantly seeks knowledge, may secretly feel stupid because he doesn't actually understand himself, and believes understanding the world will bring about understanding of himself.
This doesn't seem like Ni to me. Actually it seems more like some version of Fe, if I had to guess.
With this seeing 2 sides of every coin, Ni doms also tend to be indecisive, as all "truths" are equivalent. Their indecision comes in many forms, either in the moment decision making (INFJ),
Again, not accurate to Ni perception in me.
It does take me some time to process. There are two interconnected reasons for this.
First, Ni perception often emerges in ways initially inaccessible to the conscious mind, including visual images, metaphors, visceral gut feeling, stuff like that. So the information is there, but my conscious mind often doesn't comprehend what it is and thus how it could affect my movement. Second, Ni layers of reality are invisible in the cultural system in which I live, so I have learned to second-guess my own Ni perceptions as a default. Together, these two patterns mean that it can take me some time to consciously understand Ni perception to the point of being able to act on it. Integrating Se in service to Ni can help with this, but even with Ni-Se perception, it's still a struggle for me. However, when I am able to act directly from Ni-Se perception without having to run it through my conscious understanding, I've found that it works really well as a compass/guide to action.
(on reflection: of course, if you're a judging-dom ... I suppose at a completely rudimentary level, a perceiving-dom might appear to deviate from the judging-dom mode by accepting all truths as equivalent. But IMO that kind of description would use a judging-dom framework to describe a perceiving-dom perception and thus would be skewed away from the actual lived experience of a perceiving-dom.)
In addition to the above, I'd suggest you focus much more on trying to understand and describe
your own experiences rather than trying to define what Ni is for Ni-doms and others.
I don't see a recognizable type listed for you - where is Ni in your own cognitive function stack? Is it your inferior function? Is it somewhere in your shadow functions? Somewhere else? eta: just looked all the way through your signature at the bottom of the post. Says ESTP, which would make Ni your inferior function, yes? Apologies for missing that the first time. It makes a lot of sense to me, though.
Note: I see from your profile that you're "DJ ARENDEE." I've seen some of your stuff on YouTube and if my memory serves, you have seemed to me to have a bit of a (socionics-fueled?) obsession with Ni-doms - INFJs specifically, given some sort of assumed complementary oppositeness in our types or something? (I realize I'm mixing MBTI and socionics here, I may be misremembering but it seemed kind of like that's what you were doing. All very vague memory, though, so I could be inaccurate in some way here). Anyway, I'm not sure if or how that's relevant to your current efforts to understand and describe Ni in other people including us Ni-doms, but it seems to me there's some flavor underneath your efforts to understand Ni that may be related somehow to this other stuff. I know that's vague, but will leave it in anyway.