The film was so imitated that so many of its tropes became cliches and of course a lot of people are offended by it - namely teenage girls being sliced up by a maniac, the only one to survive being a virgin, etc etc.
But it's a very good script - I like Carpenter's writing, it's sparse and lean, lots of one sentence paragraphs, very visual, clear to follow. There's a great opening with a girl being killed and the reveal it's a kid, and we plunge into the action with Michael Myers escaping. The rest of it is hide and seek really, an excuse for virtuosity - but the female characters have some meet on them (Hill's influence?).
Main story flaw is Loomis deciding to not tell the media that Myers is on the loose - this didn't feel consistent with his terror of Myers. I'd love a spin off prequel series about the adventures of Loomis and Myers in the pysch ward!