Red Orb (Sphere of Prohibition)

On the other hand, many will start playing exclusively as mages, because their 2k burst damage is even greater.

Well, that's great! Let them play as mages. Heroes isn't just about warriors. Heroes are also about mage heroes :D. How often do you see a mage as the main character in reports? :D

Except for Luna, of course.

And regarding the burst damage and everything else, you just need to use antimagic. You might even get away with it ;)