Anjuro Katagiri is a sexual predator in the original DiU manga and anime, but this has been omitted from the movie, just as a warning to anyone wanting to get into JoJo after watching the movie.
Josuke's grandfather hits Josuke a couple of times when he comes home after the hostage scene Josuke was involved in. Later, Keicho shoots his brother Okuyasu with his Stand and beats his father.
Near the end, Koichi is ambushed when he opens a door in the Nijimura house. There's another jumpscare a few minutes later, when something crashes through the window suddenly. There's also a sudden transition at the start of the credits to a sequel hook scene
Keicho is killed by Sheer Heart Attack. The ending scene does show Koichi, Josuke and Okuyasu happily walking along together, but the threat of Sheer Heart Attack still looms large.
Ryohei is a policeman - he is beloved by the townsfolk and portrayed in a wholly positive light (except for when he hits Josuke for getting involved in a hostage situation and Josuke calls him a violent cop).
Ryohei Higashikata is killed - he is the father of Josuke's mother Tomoko. Keicho and Okuyasu's mother is said to have died offscreen before the events of the movie.
Okuyasu and Keicho's father is said to have abused his children when they were younger; Keicho becomes physically and verbally abusive to his brother and father.
Katagiri kills Mr Yamashita in the very first scene in the movie. Later, a young man named Hirata is killed by Aqua Necklace. A man who Keicho shoots with the arrow dies due to the arrow not deeming him worthy of a Stand. Later on, Josuke's grandfather is also killed by Aqua Necklace, and Keicho is killed at the end of the movie by Sheer Heart Attack.
Keicho sacrifices himself so that Okuyasu isn't killed by Sheer Heart Attack. In the original manga and anime, Keicho does the same thing except the killer is Red Hot Chili Pepper.
The movie is shot in a seaside town, so the ocean is in the background in some scenes. It features more prominently in one of the final scenes where Jotaro and Josuke are standing by the sea.