Yes but when I think of PV of being a source I think of it in an absolute sense not in methaphorical, poetic or in any way partial sense. Why? Becouse that which is manifest from PV is that which already exist (perhaps in some other form) within the PV. So if we can observe human consciousness it only means some form of consciousness is present within the PV. I would go even further and say that PV is in fact pure consciousness and that which we see manifested as inconscious (matter) is only "inverted" form of consciousness which in process of evolution has as by a miracle reverted in part into its true form - consciousness.
I think of the primal void (PV) that way too - with the caveat that we live in the opposite end of the manifestation spectrum, so what looks like a PV to us may not actually be the true PV but just a relatively subtle form of manifestation. A manifestation 'exists'
as a possibility within the PV; at this initial stage it has no distinct form, no actuality, and it requires a process of limitation (exclusion of other possibilities) to become actualised. Even an idea of something is a subtle manifestation of it.
Human consciousness exists as a possibility in the PV, but so does non-consciousness. It's interesting that you say that the PV is pure consciousness, because I have arrived at the same idea in an opposite way: rather than the PV being pure consciousness, I have come to believe that pure consciousness is actually Emptiness (i.e. of the PV). If you take away all of the features of regular human consciousness (sensory stimuli, memory, thinking, sense of self) one-by-one then you arrive at the essence of awareness, which is like a blank screen or an empty space. It is precisely because pure consciousness is emptiness that it can accommodate all the aforementioned features of consciousness. The implications of this are that 1) what we call "unconsciousness" is actually consciousness in pure form, and 2) modern science will never work out how the brain
generates consciousness because the brain doesn't generate consciousness, because consciousness is a no-thing and science is looking for a thing. The brain is a sophisticated tool for utilising emptiness. Once again I feel compelled to quote from the Tao te Ching:
"We work with being, but non-being is what we use." What we call unconscious matter is actually imbued with the 'seed' of pure consciousness, but evidently lacks the machinery (i.e. a suitable limitation complex) to utilise that seed in a way that creates any kind of self-awareness.
If there was no need for potency what would be the purpose of/for manifestation?
"Purpose" is another anthropomorphic construct which has arisen in the context of human evolution. "Purpose" evolved because 1) it gave humans a survival and reproductive advantage in their environment, and 2) as human mental capacity increased people became capable of increasingly abstract thought as an unintended consequence, and humans in turn found uses for that unintended consequence and thus promoted its further development (kind of like how electric eels have evolved to be able to give off such massive jolts of electricity). So while the earliest human notions of purposes would have been practical and immediate - e.g. finding food, having children - notions of purpose have evolved to become more diverse, abstract and sophisticated.
Like potency, purpose only makes sense when their is a concept of self and a distinction between self and other. The PV lacks these qualities: if you ask
why the PV causes manifestation, it's because the PV is a sea of infinite possibility which continuously and spontaneously bursts forth with those possibilities. Or to put it another way, the answer to the question of why manifestations occur is "why not?"