My response follows.
I've had several mystical experiences. In a subjective sense, I know (understand, have insight) that God, in some manner, exists and affects my life. I don't have faith in what someone else is telling me. I don't feel any particular need to be saved through the sacrifice of any individual other than myself.
The Gnostic mythology makes sense to me as a symbolic method of explaining what the world is about and what to expect. It's not scientific, but it has the huge benefit of not CLAIMING to be scientific. It's an internal understanding of the world within, and how that affects the world without. It's an explicit understanding that we live in our heads. The Mythology is tools to grasp the reasons behind what saint Paul said: "For the good that I would I do not: but the evil which I would not, that I do." And these tools are also there so that we may do what is good.
Gnosticism claims that the Creator was flawed and thus his creation, and that Jesus's whole point in coming here was to try and fix the flaw in creation. Solves a lot of the whole problem of evil: Stuff just isn't right, not through evil per se but through ignorance.
The Gnostic attitude toward evangelization has a lot to do with it. Seekers come to us, not us to them. The extent of our advertising is "Hey, we exist, we're an alternative understanding of what you've grown up with." But Gnosticism is self-evident: either you buy it or you don't, and it's no great matter to me either way, as there are many paths to gnosis, and you're stuck here until you take one of them. My job isn't to convince you, it's to help you when you've decided to walk the path.
The Gnostic definition of God is a good one for me. God is within and without.
The fact that Gnosticism is still growing, still having scripture written (Carl Jung wrote a gnostic scripture which some people regard as authentic), and that scripture is actually an attempt by the author to relate his experience of God, makes more sense to me than the inerrant inspired word of God.
The AJC, in particular, isn't too far out there, but is far enough out there that I like it. It's relatively new (2001) but claims an apostolic tradition (i.e., ordination passed down via bishops from the apostles). It's got tradition and innovation.
There's also some practical considerations: I don't have to go to a formal seminary, so I can keep my job. I don't expect to make it my career, it's more of a vocation.
That's a start. :-)