I'm in this for Batman. Been that way since the beginning. I have no problem saying I didn't know who the hell the director was in Batman Begins. It wasn't until the DVD special features that I started to know more about Nolan.
If it wasn't for Batman these guys wouldn't be successful and couldn't make their little expressive films with their sensibilities and styles. Burton and Nolan. Not picking on them or ripping their work but Batman is bigger than both of them. A character with 73 years of history under their belt will do that.
I've got to take issue with this statement. You seem to be implying that these guys are dependent on the fame that working on Batman films has brought to their career. Of course, working on a huge superhero movie franchise certainly helps a director and his other films become more recognized, but he wouldn't have been allowed within ten feet of that franchise
in the first place if someone didn't recognize some skill and potential in his previous work. Both Nolan and Burton had films that achieved critical success
before WB gave them the keys to the Batmobile. Even Schumacher, the most hated-by-fans "Bat" director, showed that he was successful and competent as a "general" director with other films.
Of course Batman is technically "bigger" than them. For one, it is unlikely that you'd find a director with a 73-year long body of work. Second of all, Batman, the character/concept/idea is not where the credit lies for that longevity as a character. It is the impact of the creators over those 73 years, the fingerprints of everyone who has touched the character from Bob Kane and Bill Finger, through Denny O'Neil and Frank Miller right up to...yes, Tim Burton and Christopher Nolan, and everyone in between...that have shaped the character and kept him popular and relevant for so long. If anything, Batman is more dependent on the creators that work on him than they are on him. Regardless of whether or not
you would have been interested in a director that hasn't worked on Batman, it's still entirely possible for him to have big success just based on his own merits as a director with other films (i.e. Spielberg, Tarantino, Scorsese, Fincher, Coen...etc). However, Batman as a character, is nothing without the writers, artists, and film directors that keep him in the public consciousness.