They kept playing it like "WHAT COULD POSSIBLY HAPPEN NEXT TO MAKE THINGS GO MORE WRONG???" and then nothing really that bad would happen. They had a few moments where the tension was palpable when it was just the threat of the mob and the feds on top of them simultaneously after the Robert De Niro scene where Bale and Adams talk about how they have Bradley Cooper digging them a deeper grave and how they need to get a way out. Then that tension evaporated by outing them to the mob and promptly having literally nothing happen beyond getting vaguely scuffed up. The only real consequences in that movie were for the Mayor, and Bradley Cooper.
And another thing: Amy Adams's character arc with Bradley Cooper was confusing as all hell. None of her decisions really made any clear sense to me after she said she'd go out of her way to get close to Bradley Cooper's character in order to gain leverage with him later. She does so, under the guise of Edith and basically does exactly what she wanted but then suddenly backs out of it and reveals who she really is because... why exactly? Because things got 'too real' I guess? That's not the only response to that situation though, and in doing so she sabotaged her original plan of getting close to have leverage. That doesn't matter though because that whole little plan was never spoken of ever again. It just existed and died. Then there was the whole she was hurt by Bale's character and was getting back at him through being close to Cooper and then she dropped that and instantly went back to loving Bale and it was just... She never really had any clearly defined motives in my mind during that whole escapade.
Hopefully someone smarter than I can assuage my gripes over the plot though, because I'd hate to keep ragging on a movie entirely because of "Durrr, I didn't 'get' it".