It looks like you have no major qualms with my simplistic sketch of the Big Bang and how matter has formed and will consider that common ground to build from. I thought I was addressing your point, but I'll try and address it more directly.
You state, "... that all these differences of phenomena that we believe to be surrounding us are actually coming from within us." And here we need clarification. For you I think the term 'phenomena' means anything that is made out of Energy/Matter stuff.
Unfortunately, at this level of existence the term "made out of" and "stuff" no longer applies. Which is why it becomes so difficult to clarify. We don't know what 'energy' is. I would call it a 'will for something to happen', but as an atheist, you will not be able to accept that as you will automatically presume the will must have a will-er. And I suspect that you're determined that cannot be the case. I, personally, have no difficulty with the implication of a "will-er", or of there being none. To me, it's a possibility too far beyond our 'pay-grade' to quibble about. Yet for the lack of any better way to describe energy:
the will for something to happen seems as good as any.
BANG! That will for something to happen is suddenly let loose. And so ... we have to ask ... the will to do/be what? What is it that is being willed to happen? And the answer to that question seems to have been built into the ways that this will (energy) is able,
and not able, to be expressed.
Because it is not being expressed in any/every way. It is being expressed only in very specific ways that have, over time, resulted in an incredibly complex, diverse, and very specifically balanced realm of both physical and metaphysical being. In fact, the cosmos is so complex, and yet so precisely balanced that it's impossible to imagine that any other variation of the organizing principals involved could have resulted in anything but total failure (non-existence).
And yet you keep trying to insist that it's all an accident of chance. And I find that assertion incomprehensible. I agree that chance has a role in the process that has created the cosmos (existence as we presume to know it), and that it is continuing to do so, but it is clearly not the determining factor. That energy; that will for something to happen, is being expressed as a set of existential physical phenomena: phenomena that we are currently calling 'quantum particles'. And each of these 'particles' (fundamental existential physical phenomena) has it's own unique set of characteristics,
as perceived by us, through the lens of our science. But we have no idea at all why energy is expressing itself in this way and not in a random way, or in some other organized way. But then we can't even comprehend that another way could 'exist'.
Any difference we perceive between phenomena is artificial because all phenomena are just formed from the same stuff and therefore are not really different. I just don't get this. It is nonsensical to me.
I understand. Nevertheless ...
When I was in my 20s, I read the Tao Te Ching for the first time, and it made me a bit angry. Because it seemed to me to be deliberately contradicting itself in every statement it presented.
"The tao that can be told
is not the eternal Tao
The name that can be named
is not the eternal Name.
The unnamable is the eternally real.
Naming is the origin
of all particular things."
And so on, verse after verse. I read it, but I threw it away afterwards.
But then some ten years later I had occasion to come across a copy of it, and remembering how frustrated I was with it years before, I couldn't help taking a new look. And to my surprise, this time some of it began to make sense to me. I understood that it was not contradicting itself just to frustrate me, it was presenting it's message through sets of opposites. Sort of like presenting both sides of the coin as a way of conveying the coin's 'fullness'. Still, though, I was unable to decipher a lot of the verses, and eventually I gave up and moved on to other things.
And another ten years passed, with all the requisite life experiences that tend to come with time, here. And I decided to go get a copy of the book, and look into it, again. And this time, to my surprise, I not only understood it, but I found it funny in many places. I saw that the author was not only very wise, but had a keen sense of humor about himself and the world.
My point is that sometimes these things take a long time to digest.
Here are a couple of quotes from the Tao Te Ching that I think are especially applicable to this conversation, that you might try to consider.
"When people see some things as beautiful,
other things become ugly.
When people see some things as good,
other things become bad."
"Being and non-being create each other.
Difficult and easy support each other.
Long and short define each other.
High and low depend on each other.
Before and after follow each other."
"Colors blind the eye.
Sounds deafen the ear.
Flavors numb the taste.
Thoughts weaken the mind.
Desires wither the heart."
And finally this:
"There was something formless and perfect
before the universe was born.
It is serene. Empty.
Solitary. Unchanging.
Infinite. Eternally present.
It is the mother of the universe.
For lack of a better name,
I call it the Tao."
"It flows through all things,
inside and outside, and returns
to the origin of all things."
"The Tao is great.
The universe is great.
Earth is great.
Man is great.
These are the four great powers."
"Man follows the earth.
Earth follows the universe.
The universe follows the Tao.
The Tao follows only itself."