But the helicopter disc loading is much heavier than a normal parachute and the descent is very high in a helicopter.
Yes, but, the Ultrasport helicopter has an autorotation descent rate of only 900 ft/min.
In addition, the ballistic parachutes for light airplanes must be reasonably strong.
For slow sport aircraft, the lift/drag of a large wing may replace autorotation.
It might be interesting to see if extremely large slats and flaps could be made of fabric and then rolled up like a window blind for cruise.