Neale Donald Walsch
His "dialogue series" of books seems to be likely the purest source of spiritual knowledge that exists in this world.
I wrote about why I think this in the second section of this write-up.
I'd recommend starting with Conversations with God Book 1 or possibly Conversations with God Book 3.
Communion with God is also particularly important, in my view.
Conversations with God Book 2 may be particularly important if you're interested in changing society for the better.

Darin "Stevenson"
Darin is very uniquely onto something huge regarding serious systemic issues with cognitium that are responsible for untold amounts of suffering and destruction, and he intelligently expresses it.
His mind doesn't work like that of anybody else I've ever seen, except maybe for pristine children, except they'd have to be children with a sophisticated awareness of the inner workings of their own minds and potential and of Nature in general.
I've known this guy for over twenty years.
http://facebook.com/darinstevenson
http://organelle.medium.com
http://organelle.org
A collection I made of some of his best Facebook posts (only going back so far in time): inhahe.com/darinfbposts.123.html

Iain McGilchrist
Similar to the above, but a little less profoundly so, IMO.
Though what he relatively lacks in terms of acute prodigiousness, he makes up for it with his PhD, academic works, and notoriety.
https://www.youtube.com/watch?v=v4IeuIg9nGY
https://cosmosandhistory.org/index.php/journal/article/view/290
https://www.amazon.com/Master-His-Emissary-Divided-Western/dp/0300245920/

Angels and Intuition
I've seen a lot of people pretending to be gurus spouting spiritualist memes and low-tier wisdom in my lifetime, and this person stands out as the real deal, one of the very few.
https://x.com/AngelsIntuition

Danielle Lynn
Same as above.
I particularly like the fact that she realizes that people who come across her videos do so because the timing was right for them, and that she's not just talking at us in her videos, but rather that it's an interactive two-way street on less-obvious levels of being/energy/causality.
Darin indicated something similar with one of his works, by the way, and it seemed as though the writing directly reflected by thoughts in a number of places.
He also talked about how reading such things can induce shivering, and I had been shivering a little reading it.
https://www.youtube.com/@alchemydragon

River Kenna
I really love this guy's liberated/open-minded/independent-thinking episteme, and he's very insightful/aware regarding the landscape and possible means of self-improvement.
https://substack.com/@riverkenna

Serdar Hararovich
Brilliant, astute, and extremely useful observations regarding our typical approaches to relationships and how we can improve them.
I used to know him personally online, and he's made an amazing complete 180 in his personality since then.
He used to be a very negative, cynical, probably suicidal emo, though still one with rare insight into people and the human condition.
https://www.facebook.com/serdarhararovich
A collection I made of some of his best Facebook posts (only going back so far in time): inhahe.com/serdar.123.html

Béa Gonzalez
Brilliant insights into the meanings behind various myths that we in modern society tend to dismiss as merely factually inaccurate views of things with our rationalistic, mechanicalist, physicalist, scientistic minds.
Seems to be a fan of Carl Jung and Iain McGilchrist.
https://www.sophiacycles.com/sophia-in-action

Rabindranath Tagore
A mystic who seemed very astute.
Three of the quotes in my favorite-quotes file are by him.

Unicole Unicron
Very inspired/insightful/astute.
I love and agree with a lot of what she says, even if she is a bit crazy.
https://www.youtube.com/@unicoleunicron/videos

Alfred Korzybski
I haven't read his book, but I've read some of it, and I think he was really onto something regarding fundamental flaws in how we think, especially in our approach to science.
Darin is a fan of his.
https://www.amazon.com/Science-Sanity-Introduction-Non-Aristotelian-Semantics/dp/1970164239/

Noam Chomsky
I liked his liberal and anti-capitalist views.
I always wanted to get a "gnome chomsky" garden gnome made in his likeness before he died that was for sale on some website, but I never did because it was too expensive ($400), and now he's dead and the website is gone.

Carl Jung
I always liked the concepts of his that I was exposed to, such as archetypes, the collective unconscious, synchronicity, typology, and his view of psychosis vis a vis the subconscious, though when I got around to starting reading some of his books, I just found them weird. Except for his memoirs.

Ruper Sheldrake
He seems to be good at realizing the problems and biases in common scientific thinking, and his theory of "morphic resonance" is interesting and seems to have some amazing empirical support.