It is actually more than that. Yes, Hopper was Hawkins' hero, but Jason wanted to honour the people who died in Starcourt (according to the US military), which does include Hopper. As for Angela... I get why many teenagers turn to bullying to work their own problems (I'm not condoning it, I had to change schools because of bullying). It's also a rough time psychologically speaking, but there's some lines that must not be crossed. Angela was lost.
