I have too much time on my hands.
Once a plane lands, a flight attendants walks from the front (or back, depending on which ever way the plane is disembarking) and releases access to the overhead lockers. Only when the attendent has passed the row and released the lock can people get up and collect their things to exit.
This will cut down on the bedlam and scrum of disembarking, allows for a steady and simple flow of exiting people plus a more controlled customer experience.
Would love to do this as an experiment—do you think it would work?