If I may draw an analogy with a imaginary modern military class-based  game, I want all PCs to first be distinguished from commoners as  soldiers are from civilians. Then you have a Fighter class with an assault  rifle and a handgun, and a Wizard class with some grenades and a  handgun. When they run out of grenades, they use their handgun. That  establishes some sort of basic connection with the Fighter class that I  find pleasing. I don't like the idea of a Wizard class that, when they  run out of hand grenades, they start flicking little pea-sized grenades  that appear to have a very similar if not identical effect to the  handgun. And they have grenades on their uniform and their helmet is in  the shape of a grenade, etc. That plays up the superficial aspect of  their class flavor too much. It's goofy.