The topic is basically the whole idea.
How is the most influential mage in recent Warcraft not in HoTs. Medhiv made it in and people could argue for a skin for him over an actual character but, Khadgar is more than worthy of his own spot. Having a massive hand in bringing down Gul’Dan and stopping Sargeras from destroying Azeroth in Legion is a golden ticket for our Arcane boi.