When I was 18 and a freshman at Caltech, I read a book called "Etz Chaim" (the tree of life) and found out that the ARI had already made up my religion! It was a very exciting thing for me, to have my "unverified personal gnosis" "verified" like that.
Recently, I've been making up a new system, which is based in the idea that, just like our ruach (ego-soul) has ancestors, our neshema (big S soul) does too, and they're not necessarily the same ones. These are sort of like past lives, and those soul-family trees go back to a "root soul", the god (or gods) from which you're descended. Those root-souls (gods) use human generations to breed; the gods reproduce sexually through humans, so there's also a god that you're turning into. A new, strange, alien god.
Last night, I started reading (parts of) a book called Sha'ar HaGiligulim (the gate of reincarnation) by the same student of Luria, and it turns out he totally invented this theory too! EXCITING!!!!!