Add things planes should be restricted/reduced to do.
-Wings bend under pressure(overbending possible)
-Structural damage effects fm
-Structural damage reduces limits a plane can savely be flown in
-Prop damage for all planes from wrong takeoff and landing
(Planes with 3 point takeoff/landing should use it for a reason)
-propeller bending for metal variants for saver wheels up landings.
-a collision with another plane always results in damage(except it is wood(propstrike etc))
-natural force limits for all control wires or rods .
(Preventing high g looping with some Bombers)
...