Does the stability of a mass change if the center of gravity is above or below the point of thrust?
The most stable way to maintain a hover is center of mass below and center of drag above.
What confuses many people is how a &quot;pendulum&quot; reacts while being accelerated, and how it reacts when air drag stops acceleration.
Placing the center of drag above the CG is commonly seen on aircraft tails.  This is one reason why &quot;classic&quot; aircraft tails are &quot;upright&quot;. Wing dihedral serves the same purpose,
to roll a side slipping plane back to level.
Once hover stability is achieved, one may reduce drag above or add drag below to reduce stability enough to allow controlled movement.
Leaving the Center of Gravity underneath will increase stability where when the object is not accelerating.  But &quot;pendulum stability&quot; is more properly called &quot;pendulum  and drag stability&quot;, as in a parachute.
So, in your case, keep the triangle above with light materials., but have your weight below the rotors, and just use the rotors to lift and propel the aircraft.  But if you want a separate (red arrow) source of propulsion, try to put the center of horizontal drag and CG in the same spot, and push there.