Joker was set up at the end of Begins. Bane and Talia are connected to the League of Shadows who were the villains in Begins. And if you can’t understand the villain’s motivations in these films and think it was “just because”, then you must have actually been asleep during half of them, because they were explained quite thoroughly. The only thing superficial here is your attempt at “analysis” of these films.
You are totally missing the point.
I am not saying that each individual film doesn’t have any coherence. Of course they do, they wouldn’t be great films if they didn’t.
And I am not saying the series itself has NO coherence- Bruce Wayne does.
Setting up a villain for a sequel does NOT give coherence, because they could set up ANY villain for a sequel. They could just as easily have made the third film about the Riddler or the Penguin, or introduced Catwoman and Robin in the second film. And why only 3 films?
The reasons for all these decisions lie outside the characters and story, but rather in BUSINESS decisions.
Sorry your toys are not high art.