Thompson Plyler said:
writers struggle to make the character interesting and fresh. They introduced kryptonite on the radio show to give him physical vulnerability, then they introduced different KINDS of kryptonite to exploit him in different ways, from making him evil to robbing him of his powers. Sometimes they put Lois in danger or kill her, and sometimes they get super-duper lazy and have him slug it out with some brutish villain or monster who can put up similar numbers on the squat rack. To make it more complicated for writers, the character doesn't lie, cheat, or steal. He fights with honor, believes in the best case scenario, and he's devoted to truth and justice. I'm not saying any of those make him a weaker character, but they definitely make it harder to make him interesting.
I think this has a lot to do with it: Superman is a very difficult character to write because he is so much more powerful than regular humans, so most of the standard Superhero actions are no challenge for him (e.g. the classic foil a bank robbery, or having an exciting chase sequence with regular thieves)
Because of this, while Batman, Flash, Iron Man etc. find fighting crime challenging, Superman generally only finds apocalypse level threats challenging, yet a large part of his character involves him getting involved in these crime situations that are beneath him, because he wants to help out and he does not want to see regular people suffer - these tend to come across as boring or incredibly cheesy on the big screen - although done right they can be awesome:
Thompson Plyler said:
I think the issue, Racecarlock, is that Superman's main enemy isn't Lex Luthor
I wouldn't agree with this. In fact I would argue that Lex Luthor is Superman's ultimate foil - his absolute nemesis through what Superman represents and Lex Luthor represents.
To understand Superman's motivation you first must realise that Superman is mortal. Although he may live a long time, he will sooner or later die, either from a cataclysmic event, or just old age (his lifespan in various media ranges from a few hundred years to tens of thousands, but it is heavily implied he does have a limited life), but it is certain that he will not live forever, and crucially
Superman himself is aware of this.
He knows that he cannot protect the earth forever. He knows that some day he will not be able to fly in and arbitrate peace talks between nations, 'convince' dictators to clean up their act, remind people of all backgrounds to be kinder and more considerate - because everything that Superman has achieved so far - any peace, wars avoided, criminals rehabilitated, dictators reigned in - has all been achieved despite human nature, not because of it.
Like any good Miss America Beauty Pageant winner Superman wants World Peace, but the difference is that he has the abilities and reputation to help force humanity towards that goal. Superman does not want to see the worst criminals beaten, or locked up, or detained, but
rehabilitated because that is the only indication that humanity can actually change from the crapsack, disgusting, selfish, brutal assholes human society is full of at the moment - and Lex Luthor proves that this is a war Superman is losing.
Lex has everything, but still insists on being a petty criminal full of hatred. He has never felt remorse, guilt or sympathy. His unnecessary greed and thirst for power is everything Superman is trying to weed out of humanity, yet his position of popularity and authority, and how revered he is and loved by other humans display the biggest struggle of Superman - He is trying to be a role model to let humanity follow his guidelines of goodness, purity and empathy, but as much as they look up to him, they also deify Lex Luthors' ruthless attitude and thirst for power.
Superman's struggle is not against criminals, but the very emotions and lusts that turn people to crime, greed, and hatred. He is not fighting humans, he is fighting the human condition, and the stubbornness of Lex Luthor to be involved in the most depraved evil schemes, never even consider changing his ways, yet be insanely popular and loved by humanity because of his success, just prove how much Superman is losing that struggle.