I'm sure I've got the line wrong, but as I remember it, sometime after Diane Court dumped Lloyd Dobler in Say Anything, he said "If you start out the day with low expectations, everything after that is sort of a pleasant surprise." Thankfully, my expectations for Superman movies have become so low that I seem to be beyond disappointment. I'm able to take enough of a bemused distance to have something like a rational response to Man of Steel.
After the hysterical 300 and the tepid Watchmen (let us not mention Legends of the Guardians: Owls of Ga'Hoole), I feared what director Zack Snyder would do to Superman. He was delivered from his worst instincts, I think, by Christopher Nolan, who shares story and producing credits. Nolan was the visionary behind the latest Batman trilogy (starring Christian Bale in the title role), and his work there demonstrated deep knowledge of how that character had developed in comic books since the mid-80s, and particularly in the hands of Frank Miller. Miller's influence on Nolan is clearly evident in Man of Steel's third act: the vivid, nearly silent sequence of an enervated Superman flying haltingly into sunlight to be recharged and re-energized is taken directly from a scene in the third volume of Miller's landmark Dark Knight series. This is so much the case that I wonder whether those unfamiliar with the Dark Knight understood what was going on.
I never read Superman comics very much, but was drawn in for a time by the John Byrne revival/renewal, also in the mid-80s. Before that kind of thing was in vogue, DC Comics handed Superman over to Byrne, who completely rewrote the character and his backstory. As part of that project, he developed a rather complex history for Superman's home planet of Krypton. The Krypton of Nolan and his co-writers was clearly influenced by Byrne's, especially in its visual elements. The notion of a genetically-engineered and -determined civilization was also first developed by Byrne.
My Superman is heavily influenced by John Byrne, who I believe got the American heart of the character which makes him so enduring. As Frank Miller also understood, Superman operates from an absolute moral clarity. His charisma is not his god-like power, but his absolute determination to serve and protect his nation and world. That fact makes
Man of Steel's plotline somewhat confusing. The first act has young Clark Kent walking the earth (like Cain or Kung Fu), seeking his purpose in life. This makes sense only because this has become a modern-day storytelling convention, particularly in big costume action movies. My Superman has never doubted his purpose, not for a moment.
[As best as I can tell, this walk-the-earth trope is rooted in an over-simplification of the quest motif as articulated in Joseph Campbell's
Hero with a Thousand Faces. Since Superman literally descends to earth, already equipped with all the powers he will ever have, sending him on a search for power and identity is particularly inappropriate.]
The confused-young-man bit is also at odds with what can be called a theme only if "theme" is defined as "a plot element with which you are hit between the eyes much after the manner of a 2x4." Superman-as-messiah has been an element in the character since at least the late 20th century, and was brought to the fore in his last film, Superman Returns. In Man of Steel, what had been implied and symbolized is made absolutely explicit by both of Superman's fathers, Jor-El and Jonathan Kent. Jor-El first tells his wife Lara, and then his adult son Kal-El (Superman's Kryptonian name) by way of Kryptonian interactive hologram, that the boy is being sent to Earth by design, and is to grow up to save the world. His adoptive father, the Kansas farmer, is equally convinced the boy has a salvific destiny.
If you ask me, better to keep messianism an implicit theme; cool as Superman is, Jesus makes him look silly by comparison. But I wasn't asked (again!), and I can live with it. However, I am nothing but aggravated by Jonathan Kent's insistence that young Clark keep his abilities secret, and even unused, lest he somehow get in trouble. This is just insane, and not just because IT WOULD BE VERY DIFFICULT TO CAUSE SUPERMAN TROUBLE. Superman is from Kansas as much as from Krypton, and as such is the embodiment of the middle-American virtue of reflexive patriotic service. Jonathan Kent would never hold his son back from helping others, and as good a performance as Kevin Costner turns in, what Man of Steel makes him do and say is entirely unfathomable and unbelievable.
For all that, the movie moves along nicely. It's anchored by excellent acting throughout, and all the outer space and special effects are credible and never become ridiculous. If you start out with low expectations, Man of Steel is entertaining; but that's all it is.