The Joker in TDK actually has very little time spent on him, it's just his impact makes it seem like there's more of him in that movie than there actually is. He's not the focus at all in that movie, he's the threat. The higher the threat level the greater the hero's journey is and the better the victory when he/she overcomes it. I don't think any of Marvel's films have every really had any stakes in them, and a lot of that comes down to villains that really aren't built to be much more than villains. It is what it is though, if they are happy with doing it that way that's their call, but their films are lacking a mythology outside its good guys, there's no real counter balance to who these characters are.