On further investigation, it seems #3 is more: MCAS had much more control authority (i.e. was allowed to change control inputs from the pilots by more) than the FAA had approved.
#5 is: a fault in a single, non-redundant sensor could cause the MCAS system to falsely believe the plane was stalling, and push the nose down as hard as it could. Which (see above) was harder than a pilot could override by just pulling in the other direction, as is apparently intuitive for them.
#5 is: a fault in a single, non-redundant sensor could cause the MCAS system to falsely believe the plane was stalling, and push the nose down as hard as it could. Which (see above) was harder than a pilot could override by just pulling in the other direction, as is apparently intuitive for them.