It really isn't, its just acting as fire acts. You haven't just produced magical energy then, you have just made dozens of different energies. Magic sound, magic thermal, magic light, magic kinetic. And the only rules we actually have for them is that they are magic. That's not too helpful at all, what the hell does it do, is it ay different at all? Because I am seeing no difference except so you can slap on a 'can't touch this' label

"Making the Equestrians too weak to do anything" Uh... So someone defending themselves makes you too weak to do anything? What about the Draconians? They didn't have magic. Triarii? They don't have magic. Seeders? No magic. AIF? Its reliance on magic is near non existent from what I see.
All of them are powerful and none of them have the untouchable magical energy. Everytime you mention magic, it is the most powerful thing that no one can stop and makes its users the almighty beings of the universe, and any time I bring something up its handwaved. Its infuriating.
It seems magic obeys no laws, knows no bounds, allows one to destroy what they please and randomly fill a planet with life, allows one to create a subset of energy which is unstoppable and refuses to follow the laws of physics. Even more odd is how you mentioned that pretty much every weapon is stronger with magic infusion, even when it doesn't make much sense for it to. And it cant be countered, even though you were able to give the Void Humans anti psionic weaponry which is also justified with a hand wave and, from what I have gathered, doesn't make sense either.
 I understand its magic, but can't it at least make some sense? Its just a massive Deus Ex Maxchina for the Equestrians 
Need I mention the other Deus Ex Machina?

It increasingly seems it isn't about an advantage but simply about providing a casual hand wave for every problem that comes your way