A self-diagnosed misanthrope
Yeah, I can see that. Your concerns are founded. While it could be simply wishful thinking on my part, I don't worry that Batman's gonna get a lousy portrayal in this film. No matter how many people supervise the movie, it's still a Zack Snyder film, and if Batman v Superman is anything to go by, Zack LOVES Batman. Dude has more lines than Superman in that film (at least in the theatrical cut, don't know about the ultimate edition) and if you ask even the harshest of critics to pick one scene that they thought was awesome from Dawn of Justice, they'd probably pick a scene where Batman's in it (most likely, but not limited to, the Warehouse fight). So, even if the movie turns out to be another mediocre Snyder flick, you be sure that Batman's gonna draw the praise.
Yes, we got to see a lot of humor in that trailer, but as I said, it's Warner Bros trying to reel in those that were alienated by Batman v Superman. That explains why they're making public trailers for movies that are supposed to be released mid to late 2017, where as Marvel's taking its sweet time.