My problem was putting too many plots in one movie. It would have been good if the villain was Sandman, Green Goblin II or Venom, but not ALL of them
Peter should have rejected the suit at the church and the movie end with the symbiote bonding to Brock, thus setting up a 4th movie.
Goblin 2, Sandman and "evil" peter would have been enough.
As to the dancing, would you have preferred a violent, near homicidal Peter? That would likely have pushed the rating of the movie to R and I don't think kids's parents would have been too thrilled with a homicidal Spiderman.