I will suggest that the crash was tragic but thinking that an additional gizmo in the cockpit would have prevented the accident does not address the root cause. The crash sounds like the pilot was not paying attention to either the airspeed indicator or the aerodynamic clues that the airframe was providing. Given that, the addition of an AOA display would not have prevented the accident. The pilot has to actively pay attention to the aircraft.
There was a study just published that says that the switch over to glass cockpits has had no positive affect on the accident rate. Very interesting data.
Technology will not save you from yourself if you are not already making full use of your equipment.
If the computer between the pilot's ears is in pause mode, technology won't make a difference.
Fly safe,
Wes
N78PS