I think one of the best practices a magician can do is to revisit your magical roots or foundations years later after you'd moved on to other practices and places. Lately through reading R.J.'s works, as well as revisiting Ted Andrews work and taking the Strategic Sorcery course I've been revisiting ceremonial magic. It's good to revisit it, because I'm using the opportunity to do planetary magic as well as revisit core concepts I learned way back when. To me, this re-visitation has been most useful because it's also allowing me to take everything else I've learned and readjust the foundational material to account for more recently learned and worked with practices.
I know that revisiting past work has always been beneficial simply because different experiences have been had, and those experiences shape the perspective and what is gleaned from work once read by novice eyes. It's wise to revisit works you've read, because even if you think you've mastered the content, you might be surprised by what you learn through the visitation.
Lately, in choosing to explore planetary magic and start employing it, I've found myself enjoying doing something that I might not consider experimental in the usual sense of the word, but that nonetheless is new territory for me to explore. You never stop learning and revisiting old territory can yield realizations and practices that shape your magical work.
Book Review: The Sphere of Art by R. J. Stewart
This is a must have book if you are interested in ceremonial magic or you are studying R.J.'s magical works and system of magic. What I enjoyed the most was the author's systematic explanation of the sphere of art and how it works and what the magician is doing when s/he is working with the sphere of art. I also found the appendices interesting, especially the author's encounter with Ronald Heaver. The author presents some excellent commentaries on ethics and how they apply to magic. If you get this book, I recommend reading it with a discussion group, as you'll get a lot of insights out of it, through conversation. Remember that what will make it most effectively is actively doing the practices.