I never understood these "what if x had this" discussions, how is imagining characters that have things they currently don't have matter?
It's tangentially related to the concept of a tier list. As I was saying some pages back, fighting game characters are generally sorted into well-known archetypes that have typical strengths and weaknesses. For example, one character might be fast but weak, while another is slow but strong, one is strong at range but weak up close, while another is strong up close but has to work hard to get there, and so on. The important thing about all of these archetypes is that for the most part, they are balanced against each other. If every character conformed to their archetypes fairly closely we'd likely have a game with a predictable matchup chart that was generally balanced.
However, there are always characters who exceed their design paradigms. Consider Diddy, for example. Diddy is both fast and strong. He's very strong at close range and can get there easily. He even has good defense. Similarly, compare a character like Samus. She's supposed to be strong at range but weak up close, but her projectiles are badly designed, leaving her also weak at range (in customs off, at least). This is what makes Diddy Kong an amazing character and Samus a poor one. Then there are Captain Falcon, who gives you exactly what you'd expect from his character archetype, and thus he is good but not broken.
This is how the theoretical discussion of how characters confirming to their archetypes fits into the discussion of which characters are strong. "How would you fix it?" is perhaps slightly superfluous, but it gets us thinking about just what tools certain characters need to be good, which may help us better understand the rest of the cast.
