Good to know I helped!
If you want to restrict air mobility for Earth, maybe you could instead add the ability to create a shield to protect from above? Or a fully encompassing shield to protect from all sides, but prevents you from attacking?
There will be an Earth Armor ability in the future where you form a suit of earth around yourself to for protection. Newest update was just uploaded and Earth Up Attack is new, throws a Rock high in the air to attack enemies in the air and you can also jump and kick it down. All attacks can be done from the air too now.