Yeah... I have an issue with Superman Dark, I'm sorry, it just doesn't work for me. Batman, yeah, you can make him dark. Batman can be brooding. Batman can be extremely serious.
In fact, with the exception of Mayor Adam West's Batman, making the character light and fun doesn't really work.
But this is Superman, and he is a light character. You can make serious Superman stories, you can make dark superman stories, and they work... but not when you make Superman a dark and brooding character.
When that happens, it feels like Man of Steel, a superman movie that is trying really hard to be Batman.