I think Crowley is a decent writer, but lacks any self-critical faculty. I waded through his Confessions in my youth, and found it a compelling read, though I don't think I'd bother to revisit it. I read most of The Drug ... a few years ago, and ended up treating it as research for my own writing (and my own career in untrammelled evil).
If Crowley interests you as a character, I'd recommend Somerset Maugham's The Magician, which is based on him (and qualifies as fantasy, especially towards the end). I like Maugham's take on the real Crowley: "A fake, but not entirely a fake".
Yes, I’ve read
The Magician and was particularly interested in Maugham’s introduction, which, if I remember right, gave a sense of how Crowley was perceived by contemporaries on the scene. Strangely, I am quite well read around Crowley, though very much as a tourist, not a practitioner (I cannot stress this enough). It’s a long time ago now, but I was touched by
Israel Regardie’s biography of him which (memory may be faulty) emphasised the spiritual seeker side of him (you may know this: Regardie was briefly his secretary as a 17 year old), and I continued to buy the biographies as they came out every few years, in an attempt to understand what was going on, and generally read around him and his peers, up until
Lawrence Sutin’s biography (Sutin also wrote the biography of Philip K. Dick), at which point I decided I’d had more than enough and sold the various stuff I’d accumulated. I never read
The Equinox or
Magick in Theory & Practice (tedious writing). Like you, I did struggle through the Confessions.
I still have a lot of respect (perhaps misplaced) for Regardie who ended up as a successful Reichian therapist in California. I regularly buy the more anecdotal (less technical) books of
Lon Milo Duquette, as they get published, as I find them a surprisingly good read, describing how he incorporates Crowley’s magick into his life. Sadly he has probably run out of suitable memories to print by now.