Like vee said, all esoteric history is an mix of different cultures, and in fact, I believe most paths to enlightenment share the same purpose and method. Trances, colors, hallucinogenics, repetition... all these are things that exist in most cultures, while their purpose in, in some way, to unite with the Divine.
I have written this in the Totems thread that while people get their feathers ruffled at this or that native culture being appropriated, few ask themselves about doctrines that were appropriated in the past and have been fused into the Western Mystery Tradition. Kabbalah is a prime example of this. Many people who are not Jewish study it, and I must admit I do in a non-religious capacity, but there is no doubt that it is inherently Jewish. It is just difficult to get around. In addition, what is taught in the West is merely one school of Kabbalah, of which there are many, dealing with such diverse topics as sex, actual magick, society, talismans that do not include a red string... really, it's just so big, and anyone looking for New Age appropriation, look no further.
However, the Golden Dawn, and others took it, codified it and made it somewhat easier to understand, and I do thank them for it. Just this morning I read Crowley saying in Magick Without Tears that he had no interest in Jewish theology or ritual, but did use Kabbalah daily. Now, honestly, I think that's a ridiculous statement; it is practically impossible to separate the two (the Tetragrammaton is part of Jewish theology, the "oneness" of God in Kabbalah... in short, most of the most learned (Jewish) Kabbalists were quick to point out that nothing they wrote contradicted the Torah, although at times it may seem like it.
Now, the point I'm trying to get to is that I am all for quilting a unified worldview made of many parts, but like any Tarot deck, my motto is simple: do the work, do the homework, if you have something to show for it, great. Crowley did when he fused Kabbalah with Thelema, alchemy with the Three Gunas and in a number of different ways. However, unless you really, really know what you're doing, the results could be ridiculous, and usually are. Waite did it well, so did Mathers, Wescott and Crowley. I have yet to see, even among acclaimed Tarot authors, anything coming close to that level.
I think that in many respects, New Age has nothing to do with spirituality, but with making money. People nowadays seem to have no patience for poring over books for years on end in order to make a minute spiritual discovery; they want it instant and fattening. There are still Golden Dawn caliber occultists who haven't "sold out" but they are few.