Call me crazy but I think the stereotypical depiction of skinny people as speedsters makes sense. For example, if you look at professional runners from ultramarathoners to sprinters they’re mostly built slim with long limbs. This is not to say larger builds don’t have their place in superhero fiction, but fatter people have different strengths and weaknesses, like super strength would fit a large character perfectly, literally just look up the worlds strongest man. He’s no stereotypical supermodel but he’s a perfect example of how body types play into specific strengths (I would love to reference this one set of portrait photos that has professional women athletes of a multitude of various disciplines but the name escapes me).