I agree with you 100% about the basis of what you are saying about UC.
It is something I discovered partly because of the books I was reading at the
time (on matter and the Universe) but mainly because of the way I used to
trip. After a while it did occur to me...... So!.....Now what? To use
your words "an awe-struck cul-de-sac". I found it
difficult to find value in the experience other than its inducement of intense
ecstasy, similar to a heroin rush I imagine!
But, after my period of abstinence and particularly in more recent trips, I
find the ability to "still the mind" invaluable before setting off
into the unknown. Not only as a means of navigation but also as a way of
viewing the experiences from a universal perspective instead of
the rather limited human perspective that most people take with
them.
This does not mean to say I don't value the human perspective.
After all, I am human too, and I agree with you that we are far from the limit
of human possibility, I just feel that these possibilities will only be truly
realized whilst coming from the other direction - i.e. without the human
baggage. If those other realms are depicted as an infinite
maze of possibilities, then UC is the bench at the centre where we
rest and take stock of how we got there and where we go next. It is
in this sense that I use the term core experience and also
because, of all the weird and wonderful experiences I have had, this
remains the most profound.