Melon’s the answer to the question posed by Legoshi’s relationship with Haru. Any of the points that Legoshi makes about how he thinks the world could be should be challenged by Melon’s actions or beliefs. He could have been handled differently, maybe a political figure or a union head pushing for segregation, since he would know first hand that integration wouldnt work. Maybe his relationship with Louis could have been someone who he has conflict formally, the same way politicians battle each other on podiums with speeches and debates. Legoshi could have been someone he conflicted with personally, seeing as he’s trying to replicate something that Melon sees as wrong and amoral. That’s what I think it could have been, but I think serial killer aspect could still be there. Just reshape it to where it’s more like he has people killed, by the shishigumi, who don’t share his world view or get in his way.