^ you're right. Each event is dedicated to a certain group of characters, and sometimes just one specific character and that's very amazing. It gives the world so much more depth.
@V-Oblivion: I'd argue that out of all Arknights characters, the ones most likely to be the main characters would be Nian's family. They're supernatural beings that's fighting to survive and prevent the revival of a terrible god hellbent on either dominating the world or destroy it.
Or maybe the Abyssal Hunters, but I don't really know much about their lore, aside from the fact that it invovles Cthulhu.