Electro was intended as such, he represent the fan who lost the true nature of super hero. He 's getting obsessed because he lacks attention and will end over confident because he was allowed great power. More precisly energy, wich is the theme of this movie.
At the opposite of Electro you have a child who built a wind turbine, a clean power source, and he wants too be like his hero not be admire by him. The movie is about fining that inner child back and has Spidey tell him in the end "it's good to be home". The child brought him home.
Goblin fit the theme of the story as well, both Peter, Gwen and Harry are possessed by phantom of the past. Peter and his parent. Gwen and her dad wich litterally come back like a ghost. Harry by the malediction of his father wich he canno't control. He's out time. Times keep coming back, Peter find back a video of his father, he and Gwen have to save two planes from crashing (if you didn't make the link his parent died in a plane and Gwen was supposed to leave by a plane, it symbolize change).
Youps other theme of the movie: time. They litterally end up fighting in a clockwork. Harry was greatly brought in that light since he represent Peter fear of runinng out of time.
Running out of time. Energy source. Death. Childhood. Growing up. And they tie it all pretty well, simply but well.
The child with the wind turbine represent clean change, because he is true to his heart, he can let go, like the wind. It is the opposite of Harry who brought Peter in a big mechanical clockwork. Wind turbine vs clockwork. That's actually a pretty powerfull symbol.
Rhino at the end enhanced this cyclical theme of time passing, as we saw Peter mourning Gwen's death and the season passing. And if you didn't noticed he is a bad guy and also in a mechanical/machine suit.
But keep on bashing what you don't understand with no constructiv criticizm.
