so i also get annoyed that it is explained too many times. if you are that dumb you should not be watching this movie. although the scenes with the old guys at the tower, felt very comic book to me. so i think that's why i let it go. the way that entire sequence is laid out feels super comic book to me. the way it is cut, the dialogue, all of it.
as far as the device goes, i don't think it is that unrealistic of a device. now i think it would be hard to construct something with that much power behind it, but the concept itself sounds like a pretty real thing to me. it is like using an EMP weapon instead of a nuke. It doesn't lay waste to the area and kill everyone, but it will make it impossible to fight off any attack. it crushes infrastructure/resistance, which was their goal. this kind of tactic has been used for thousands of years when trying to take on a larger opposing force.
also, crane wasn't dumping anything in plain sight. he had total control over arkham and was dumping it in some basement chamber that no one would ever go. he was probably the only one with the key to the floor (if you remember he has to use a key to take Rachael down there). considering the toxin itself was inert unless it was absorbed through the lungs, no one would have ever known one way or the other.
Ah thats a good point about Crane and when he used the key. Yeah I guess he did have pretty much total control. I will let that one slide.
I see your points on the weapon. I don't hate the weapon, it's just not my favorite. I do love how so many tiny details are all wrapped up into it, like the blue flower Bruce picks at the start of the movie.
I also forgot/liked how the League was responsible for the depression and how the Wayne's were fighting against them and not even knowing it.
BTW this movie has so many great lines. Everything out of Liam Neeson's mouth is great. Nearly everything out of Bruce's mouth is also great.