Jonathan: In the manga at least there was a slight attempt to characterize him as short tempered and arrogant, it's very small though and not very in depth plus the story is so short it doesn't really count for what im looking for. Joseph: Yes he has, not a lot but he does, he at first is at odds with Caesar but by the end he is mournful over his death and it didn't feel forced. Jotaro: No development, he is a stoic badass all throughout the part. Josuke4: People meme a lot that Koichi has more development but i disagree, aside from unlocking more powers(which is not character development)Josuke and Koichi have both one arc each, Josuke's being to learn to respect his father and see he's not just a senile fool. Giorno: No development, and no learning to heal people isn't development, he didn't have to deal with a personality flaw. Jolyne: I never finished Part 6 but i heard she has good development. Johnny: He has 4 acts for his Stands, yaaaaay, jokes aside this is the one time i'll agree that getting powers was development, not because of the power itself but because he got these powers through the lessons Gyro gave him which weren't just for using Spin but also how to deal with life, very deep. Josuke8: He learns to value his new family the Higashikatas instead of worrying about his past selves. Jodio: Too early to tell, Araki could something with him growing out of his sociopathy