The whole debate about this isnt even funny anymore because of how wrong one side is. The World Engine did 95% of the damage/death to Metropolis, not Superman or Zod fighting. The damage done to the city was severe so the audience knew Zod and the others meant buisness. This was a serious threat not only to Metropolis but also the world. Quite the contrast to Superman Returns where the threat is ideally located miles away from the city and the only damage it does to Metropolis is broken windows and broken gas pipes.
Also there is this clip
http://www.youtube.com/watch?v=3MJjkqVX6Ro
But thats fine because it's cool and all, doesnt matter its Superman destroying 7 skyscrapers and a city block (when he slams Darkseid) just so he could "cut loose" for a moment.
The destruction during the final fight was huge - and needed - to highlight the power of the two super beings. Give the Hulk flying ability and Superman's speed, what would happen? The answer is what happened in Man of Steel.
And in the end, while this may be a more grounded and realistic Superman, its still very much fiction, and still very much a comic book movie.