Interestingly, they appear in the order that they posed a threat to batman. Ra's al ghul and the scarecrow obviously, but Harvey dent was a rival to batman for gotham's affections before the joker arrived. And at the end of TDK, batman had activated a surveillance system, threatening his morals, and thus becoming a threat to himself. Then Catwoman met bruce wayne before bane did, and thus threatened him first. Also, tom hardy was actually substantially shorter than christian bale, they had to use camera angle trickery to make him look about the same size.