I'm a little surprised that no one else has commented on a fact that I believe is fairly obvious when you take a close look at the card: Hermanubis is nowhere to be found.
Crowley says Hermanubis is on there, and Hermanubis is certainly there in the Golden Dawn description of the cards. He's even found on the Rider-Waite Fortune card. But not on the Thoth version.
Hermanubis is a jackal-headed god, and not an ape. When I spotted this inconsistency, I looked high and low for any evidence that Hermanubis was ever depicted in a simian form, but wasn't able to find any. I can only find depictions of a human form with a canine head. The figure on the wheel is the Ape from the Magus card. So we still have an attribution to Mercury (and thus, Sattva), but not the way Crowley tells us.
I can't help wondering if there is a bit of a visual pun here. The Ape is the cynocephalus ape. Cynocephalus means "dog-headed," so perhaps we're to interpret the figure as "aping" the dog-headed god.
I'm not quite sure how to interpret this change. It may be an indication that there are even more blinds to be found on the found--the Ape of Thoth misleads.
The best I'm able to figure, per the BoT: "the Gunas revolve." I find it tremendously difficult to find a particular, definite Guna to attribute to any of the figures. Each can represent any of the gunas, depending on how you want to hash it out. One could spend a tremendous amount of time going round and round in circles trying to figure this card out, but the guna of each figure will continue to transform into the next guna as you consider the card closely. But we don't really want to be going in circles. From the list of short verses found at the end of the Book of Thoth with the common divinatory interpretations: "The axle moveth not; attain thou that."