On the contrary. I think Batman is the LEAST likely to be put in auto-pilot. He is the character most people are interested to see, and the only one with profitable movies in recent history on his belt. If it wasn't because WB didn't anticipated the success of the Nolan version and the avengers movies, I would have guess Batman would be their advance franchise to justify having a JL movie. Instead, they are putting all their hopes in the Superman movie, because its the only other character they seem to get right once in a while...
That doesn't change the fact that part of the charm of the Avengers movies was to see all the characters being played by their respective actors from movies in recent history. As such (and I haven't kept in touch with casting news for this movie), but I hope they are saving a pretty big check for Bale and another one for Nolan, because if those two are not involved in the next movie, all the marketing in the world won't save it.
If anything, most other characters are allowed to be on auto-pilot a lot more. I don't expect Martian Manhunter and Wonder Woman being more defined than "I am like Superman, but green/woman", so I don't expect more than 10 minutes will be dedicated to those characters.
In other words, I am too a little bit tired that the only character that seems to be in any way relevant to WB, DC movies and the JL in general is Batman; but they can only blame themselves for that, and it would take them a lot of years for them to make the public care about anything new so, if they want to make a JL movie before even Avengers become irrelevant, they are going to use current Batman, current Superman and introduce a bunch of other characters; and the movie will be called "Batman and his Superfriends"...