There was a little too much reliance on the sun, and there was no excitement during the fights. The minute superman was put in a cage, I was able to predict that metamorpho would turn into a sun to help superman. That level of predictability is not good for a major turning point in the movie.
You want superman to seem friendly, and connected to the people of the city and i understand. However, he still needs to give a level of indestructible.