I think you should focus what you're asking, if you don't mind me saying.
If you're looking to study a deck, that's one thing, and the many sub-schools of the Golden Dawn afford a great many opportunities for learning.
On the other hand, if you're looking to study Kabbalah, then any GD deck is a viable choice, including the RWS which does have the Kabbalistic elements, albeit somewhat hidden. If you already own both the RWS and the Thoth, that's a whole lot of Kabbalah right there, and you don't actually need a special deck for it. Although he compares cards from four decks, Wang himself does not detail specific symbols in his book, instead dealing with the overall structure, which is inherent in all the decks. Dion Fortune isn't that deck-specific either. The Kabbalistic structure exists even in the TdM.
I study the Thoth, for example, but most of the study does not deal directly in Thelema, but in basic Kabbalah, as I am at present studying the paths, not necessarily the visual commentary to the Book of Law that is the Thoth deck. The elements that go into making the Thoth are identical to any GD deck, such as the astrological attributions that reinforce the Kabbalistic ones. Same goes for the RWS. Just start, and the rest will follow. Get one if you want, but I don't think you need a new deck.