I've been doing some photo analysis of the final second of dashcam video of the accident. What impresses me is how rapidly the nose falls into the depression at the end of the runway.
A tricycle gear aircraft is roughly balanced on its main gear with the heavier end on the nose gear. of course, but this means that there should be significantly less than 1 g worth of downward acceleration at the nose of the aircraft unless there is substantial uplift at the tail, heavy braking going on, or perhaps the main gear have hit some substantial obstacle which pitches the aircraft down.
If I was to run off a runway at speed, I think I'd be doing it with full aft stick and trying to keep the pointy end up in the air. The pitch down into the divot at the end of the runway is strange and almost certainly caused the high percentage of fatalities among the crew.
