What I thought the film did really well was the fact that Kal has to keep things in check all the time. Not just because of the fear he'd create...but the damage as well.
Example: He let that guy in the bar throw the beer can/bottle at him and shrugged it off. Then he went outside and vented by putting the guy's 18-wheeler in a tree.
If Kal ever "cut loose" like Wolverine, Deadpool, or even Batman, it's not just people who'd die. Mountains would fall. Wind patters would change. Climates would shift. Species would go extinct.
If it wasn't for his upbringing, he'd be like Zod.
Which is what makes Superman a hero.
Because how many of us would do what he does if we could do what he can?