This subject has been discussed several times, and nobody is suggesting ONLY Engineers do a Preflight, that would be as stupid as the proposal that ONLY Pilots do a Preflight.
The current system that has served us well for decades should remain, that is at least 2 independent checks, 1 by a Pilot and 1 by an Engineer.
As the the remarks about missing things, I could quote many cases where Pilots have missed things, THAT is the beauty of the current SAFER system, 2 INDEPENDENT INSPECTIONS, who really cares who picks it up as long as one of you do.