Hmmmm. I can understand why you might think that, but IMHO, it fits both symbolically and stylistically.
As I already said, it looks like the misty landscape from behind the Fool which is significant all on its own. On the surface looks like it could be for any deck, but if it is the Fool's background - the significance is loaded with that 'mystique'. It is just much
more subtle. I like that subtlety. The sense of change - flux - and the mutable nature of geography and landscape is very
gently but effectively presented. The power of a waterfall in Nature, the force of water (and wind here!) deliver a deep emotional experience - love - for the whole.
The Thoth 3 of Cups is the "Lord of Abundance" and that allusion to the Empress, deep passion and love - even the conditions for creation - are all present. I personally love this kind of landscape painting, so it speaks to me. Not every card will for everyone. Our unique interpretations are what make it so much more interesting! But to say it is NOT Mary El I'm afraid we'll have to disagree!
I had no idea you were interested in Qabalah, MiShell. It will be interesting to hear your thoughts.