I will give you my perspective and the practicalities of all the questions you have here and how they support for the "normal" person - first of all, people believe in gods and religions, don;t make "ordinary" people seem so useless and not capable. "ordinary" people are capable and able to understand more than one can imagine.
There is an inherent point of common sense in every human.
You say you agree with the "IDEA" of the part where it is is saying the mind is real, I point this out because your words are saying you have not identified your own mind yet that exist within you and thus still somehow think the mind is an idea? when in fact it is here, it is a software programmed into you and running you, its a fact, not an idea, self-confirmation is needed here, look at thoughts, thinking, they are happening, yes they are not real as in what matters as life and can be deleted, but they are here, thus real, you can confirm it yourself. what makes them not real is when you delete them, then they do not exist anymore.
Now on to your second part. "What is the practical purpose/reason for disclosing an existence that ordinary humans cannot see/verify for themselves? "
It is to make them aware of the parts that they cannot see/verify as to stop the mind control and brainwashing. The human sense as the "five senses" we have are literally designed the way they are to keep us trapped in limited senses and to seeing the rest of reality that is here, like wearing a mask, so here it is to bring awareness to humans of an existence that they are not aware of and that the slave designs of the forms of the human bodies can not hold control any longer. It is in fact the things we can not see/verify that is controlling is, as that is the design of deception for the organic robot human.
Take a look at yourself, how did the information of this existence that you probably still can not see or verify, but just the awareness of it, how it has supported and assisted you into already breaking so many ideas, believes and opinions within you from this new information. this is because the new information is defusing and breaking apart the brainwashing and mind control perceptions of reality within the "ordinary" person once it is heard and seen, not immediately, but it expands the being to "remember" more of existence than just seeing their brainwashing and mind control.
Also, those with a hint of self-honesty and introspection and self-intimacy will be able to self-honesty take the information and SEE within themselves and confirm for themselves that it is so (when designs and constructs are explained) and thus an understanding of the inner workings and existential workings are now more understood, and thus the controls, designs and systems are less able to simply direct the person, as when we are aware of it, we can see it in work and thus take action to change, stop and not follow the pre-programming.
The next point:quote: " What is the starting point of the primary three interview series on EQAFE Quantum Mind, Atlanteans, and Reptilians series that go into this interdimensional perspective in absolute detail? Because speaking as an ordinary human, it's fine and dandy that colours and shapes are described, but the practical application of such knowledge escapes me. And what justifies the time commitment to read Heaven's Journey to Life from Day 1 for the ordinary human being? I ask because I'm not ordinary in the verve I live out when something interests me, I've already made the decision to read from Day 1. But most people in the world probably want something that's going to benefit their lives in a practical, measurable way, like how the Lessons in Desteni I Process Pro quantify your understanding of your own mind." end quote
The inter dimensional perspective is because the inter-dimensional existence is where you are being controlled, on a multi dimensional level, that's where the Reptilians, Atlanteans and so forth played god and created what is here today as the physical existence. If you want to rebirth yourself as LIFE as GOD then you need to understand creation and existence in detail as a god to be able to stand equal and one as existence, understanding all that is here, it is re-education of the human, how does this support us? well once again take a look at your own process throughout your entire life, how has any new inf9ormation ever helped you? it changes your believes, ideas, opinions and your perspectives, and so you change, your actions changes, your core designs are being changed through new information, the words.
Religion (HISTORY) is what is sued to educate humans into control, brainwashing people and instilling mind control, through giving the real history, story and designs, the current mind control is broken or at least penetrated to break, those with self-honesty will be able to handle it, those who do not yet have self-honesty will run and miss the practical point of education and how education is what shapes the human being.
Desteni has many aspects to it and that has been very clear from the beginning - they are: Re-Educating the human , Practical/Living re-birthing self as life/breath and then taking action (EMS, ELF etc). They all fit in together in the end as one thing, but we are all at different levels of our process in different times, so some can handle only one aspect, others can handle more.
This is my answers.