Reddit reviews Asclepius: The Perfect Discourse of Hermes Trismegistus

Since you appear to be leaning more Gnostic, rather than Golden Dawn, I would definitely recommend that you begin with the Corpus Hermeticum. You will have to be discriminating with what you read, because the word Hermetic means so many things these days, often being used as simply a stand-in for occult or esoteric.

Here's a pretty good article with reading suggestions. Like the author, I caution against starting with The Kybalion. It's a modern text that isn't very closely based on the ancient teachings that have so many commonalities with your own Gnosticism. It's more for people interested in a modern western esoteric brand of Hermeticism.

Once you've read the Corpus Hermeticum, if it intrigues you and this is something you want to delve deeper into, I suggest moving on to the Asclepius, if your translation doesn't include it, plus a book on the origins and history of Hermeticism. Then you've got a good base to dive into other source texts, like the Hermetic texts in the Nag Hammadi library.

As for putting your mind at ease, I'm not a Christian, and I come to Hermeticism from a 20 year polytheist background, so it isn't my place to tell you it's not witchcraft or evil. What I can tell you is that Gnostic Christian communities found a place for Hermeticism in their practices and philosophy, as did many more mainstream Christians, as you know. I can also tell you that there's little about the philosophical Hermetic texts that has to do with thaumaturgy (miracle working, magic). While I don't speak for all Hermeticists, my own Hermeticism (which is informed by the ancient sources) is about uniting with the divine and taking the place in this world that the divine intended for me. I personally do things that you might consider magic, with the intent of effecting change in myself to improve my link with the divine will. You don't have to if you don't want to.

Asclepius: The Perfect Discourse of Hermes Trismegistus