I dont have more faith in the ball/plate than the regular hook setup. The trapeze harness can trap you anyway, what is needed is a quick release harness that is as simple to escape as pulling the reserve on a parachute rig. That dont solve all problems either, as you can get trapped in sheets, beneath sails (especially spis) and I know not what..
As mentioned earlier, everything we do, and I mean everthing, has some elements of risk. We can minimize them, but never eliminate them.