The reason I was so attached to the Sphere system to such an absurd level was because I hated the idea of Elemental Magic as it is commonly used in fiction; with Elemental Magic, we get stuff such as Earth/Wind/Fire = Healing (Water gets a pass, because a lot of medicines are water-based anyway), Fire/Wind = Divination (Water gets a provisional pass), Fire/Water = Mental Clarity, Wind = Mind Reading/Postcognition (the ability to see past events in a place), and other stuff that makes no sense. We also get new Elements like 'Heart', and 'Energy' whose purpose is to create another set of absurd correlations, such as Heart apparently being able to make electronic items work without electricity (W.I.T.C.H, the original comic, not the cartoon).
Same for adding Light/Dark elements; Light and Dark Elements are a mashup of several associations and functions, to the point where literally anything can fit into Light and Dark Magic; Healing, Destruction, Illusion, Protection, Conjuration, and Alteration.
Note however that I left this RP, so I have no right to speak out against your plans. I'm really sorry. It's just that I'm against the idea of Elemental Magic as used in Winx Club, W.I.T.C.H, and Final Fantasy.