Regarding Passengers Reaction to Fire
People in general are not rational in the presence of fire. There's no changing that. We have to cope with it. It takes years of training and experience (and preferably a load of protective clothing and breathing apparatus) to be able to behave rationally in the presence of fire.
Prosecuting people who obstructed an evacuation by collecting their hand luggage will not change anything one little bit for the next evacuation. Locking the overhead bins is the only answer to that problem. And I would say that locking them individually with a key is important because everyone then knows that there's no hope of opening them. It's also cheaper to fit.
Fire on an aircraft is difficult to manage well when on the ground. If the aircraft is stationary and there is no visible progress towards evacuation, you're always going to be moments away from pandemonium. That's just human nature. Yes I know that doesn't square with people then stopping to grab their hand luggage; that is also human nature.
Here's an idea for discussion; I'm not anticipating universal acclamation! Perhaps there ought to be a mechanism that, if the aircraft is stationary and one of the doors is popped, cuts off fuel to the engines and sets the parking brakes. The guys at the front are normally in the worst place in the aircraft to evaluate the severity of a fire, and a means for the cc to take the matter out of their hands might make the difference between a successful evacuation and a total disaster.