1. Is this movie enjoyable without having seen the series? Not even in terms of plot, but is it a decent introduction to the characters, or does it rely on you knowing their personalities?
2. Does it feel like a miyazaki film? His films have a pretty distinct style, is that style present here?
1. No, but it helps if you've seen at least one episode of the series and read an issue or two of the manga.
2. It feels like a prototype compared to his later works (his trademarks are all present) but it's still a fun and enjoyable story.
You definitely DO NOT need to read the manga or even watch the series to enjoy this film. The reason being is that the titular character acts so differently here than he does in his own series and movies.
It's definitely a great film to show to people of all ages regardless if they're a fan of anime or not. I like the Manga Entertainment dub where David Hayter voices the character.
It definitely feels like a Miyazaki film from the story elements to the character designs.
1) I'd never seen the series. In fact, I've heard it works better if you haven't seen the series since the personalities are a bit different. But I still enjoyed it.
2) Not that much. His fingerprints are on it, but its tone and even the pace is not exactly what we're used to from Miyazaki.
Can't stop the signal.