The fact that Begins was Nolan's first blockbuster was why it worked. Nolan was coming off of darker, more mature psychological thrillers and his experience with these types of films was what made Bruce's emotional journey work through the film. It has more of an emotional core than it's sequel, although Nolan managed to grasp back a hold of that core in TDKR. Also, Nolan hadn't had the experience shooting all kinds of action, which is why the film's action is subtle and works in a great way. It's not overdone, it's not over-the-top and there's no way it needs to be. By the time TDK rolled around, Nolan was experienced and ready to pull out the big guns.