Oh boy, symbolism! You know, I hated talking about this in high school.
So, Smokey probably has the most heavy-handed symbolism of all my characters: he's literally a volcano. Everything from his kit to his color scheme was designed to emphasize that. Even aspects of his personality were designed with that theme in mind, most notably his anger-management issues. However, there are other aspects, too. To make another comparison, volcanic soil is some of the most fertile in the world, and as long as the volcano doesn't erupt again, life can thrive near it. Similarly, if Smokey can learn to keep his temper completely in check, he'd find that people might actually consider him a valuable member of the community. In a world filled with giant monsters hell-bent on driving humanity to extinction, having the biggest gun on Remnant at your back would be considered quite the boon, no?
Moving on to his kit, his semblance makes him like a mountain-- immovable and unshakable. It provides the base for him to fire his weapons, which act as the force of the eruption. His kit allows him to hit way above his weight class, thus he's able to easily take down Grimm that others would struggle with. This comes at several costs, though. Like a mountain, Smokey's not exactly mobile. He's at his strongest when enemies come to him, since he bring the full force of both his weapon and his powerful, semblance-enhanced grab. Furthermore, his gun, like the flow of lava, is indiscriminate with its damage. For instance, if an ally is engaged in melee with an enemy, and Smokey tries to shoot the enemy, the spread of Matchstick would probably hit his ally, as well (unless Smokey got up close and personal first, of course).
And that's just Smokey, I have four other characters, but I'mma leave it here for now, I'll come back later, eventually.