I don't think Bam is above the rest Just level wise. The others likely wont catch up to many of his skills ever. Such as number of Bangs controlled at once, Shinsoo Black Hole, or this type of reinforcement he uses (likely another exclusive feature of irregulars). Even If they are given the same training and battle experience, Bam will still Shine above.
I think he COULD be a Fisherman If he had to, but not an outstanding one. More like those High rankers that can fullfill any position, but still have Wave Controlers as ideal one. That's Bam.
Imho, Spear Bearers are those that can hit from Very afar but also Very strong single attacks. Red Velvet sword, for instance. Bam's attacks are area attacks, never a precise focused hit. But he has strong direct hits, such as Hwajepgongpasol. Amigochaz and Novick have strong close range hits too, and I don't see them fighting from so Far away, despite being Spear Bearers. So Bam could in theory be one too I guess.
He also can freeze enemies and transport people like a lighthouse, or spot invisible enemies such as an Observer, so perhaps he is really going to be High ranker, which requires all positions fullfilled, eventually. As long as he doesn't require class specific knowledge, such as actual Spear throwing or lighthouse programing, perhaps he might.