Batman cant really be as fun as Ironman, unless they do a movie in the adventurous style of B&R or Inc, which wouldnt go down well with the general audience. So Batman being... well batman is fine with me. Coming out of TDK i was heartbroken, had a lot to think about and wasnt smiling. It was catharsis more than having fun.
So personally i really loved the story and what happened in TDK.