Perhaps the gourd will stop crashing your game once it's name is translated? *Shrugs*
Anyway, about the elements, yeah, Earth is more of a... well, earthy thing instead of nature/grass, yeah. And along the same lines, Wind/Elec is definitely more of an Electric thing. Aya's wind attacks aren't even Elec elemental, for one, and every single spell in the satori list (Which is about my only point of reference *Shifts eyes*) that's Elec deals with electricity-type stuff, except for Tornado, which is the single exception. A much better representation for the element would probably be a lightning bolt sign thingy.
I agree with the six-point star shape thing for Mystic that was suggested.
Although I think it might just be better to go with short abbreviations of the words to put in there instead of little icons. But, as there is little space for letters, and as you've already made them in the first place as well ^^; It's not a bad idea at all!