>>100483816BW getting kidnapped and put in a cell all happened because ScarJo got unexpectedly pregnant. Notice how many shots of her in that part of the movie are framed from the chest up, or are close-ups of her face. She apparently had a whole different role during that part of the movie where she was much more active that got scrapped.
Also, the Hulk/BW romance was poorly executed but people don't give it credit for what it was actually about. I think it was intentionally awkward (nothing else explains why two romcom character actors had such weird chemistry) and it was supposed to be this sort of bond over their shared guilt-heavy past. They pursue a relationship and entertain thoughts of a normal life as a way to absolve themselves of their past, but Natasha realizes the only way she can do that is to continue being a hero, so she ends it with Bruce and joins the fight.
