Take Velen. He's a powerful priest(?), a wise leader, a really impressive beard and a whole bunch of things. But if you were to cut away all that stuff and just look at his personality, he comes off as Space Jesus. In other words, he's the wise old guy. Varian is the papa wolf, and that's really all he has going for him. Anduin (or whatever his name is) is the rebellious youth. Garrosh... screw Garrosh.
The point her is to make you look at your character, ignore everything that "makes them tick" and just realize the base around which they rotate. What is the center of their personality? Why is that the center? Has it changed?
The best way to tell is, if you were to remove it, your character would fall apart. If you took away Velen's Wise Prophet gimmick, everything else would go all mushy and disconnected, if it even made sense.
Myself, I've got Ozuna, who's the matronly healer. Sure, there's more to her than that, but that's not the point of the thread. I'm also swinging around a mischevious kid who's bitten off more than she can chew, a badass bald black leader dude, and a bloodthirsty power-seeker.
So what about you guys?
Edit: In my mind, magic=magician. The distinction is rather small. I originally thought Furion was a mage.