Talk:JoJo's Bizarre Adventure: Diamond is Unbreakable - Chapter 1 (film)/@comment-30230931-20161114201419/@comment-4045389-20170110163340

"Picked up Something Bad" is actually a very crucial turning point in Josuke and Joseph's relationship; Joseph slitting his wrist to help Josuke find Shizuka, risking his own life in the process, is what makes Josuke start to warm up to the guy and see him as something more than just some senile old man.

"Cinderella" is the arc where Yukako is able to amend her relationship with Koichi; if they cut Cinderella out they'll have to cut out Yukako's first arc as well and come up with some other way for Echoes to mature to Act 2.

If Mikitaka is cut from the story, then "Let's Live on a Transmission Tower" will have to be either heavily rewritten or deleted entirely, due to how crucial he was to the latter.

The other arcs that you mentioned, however, could be cut in the film adaptation, since they don't have much impact on the story as a whole.