First, a little explanation of the terminology. The FAA will give a pilot a gyroplane rating after he demonstrates his competence with an autogyro. I will focus on the same rotor for the gyroplane that I did last month for the helicopter, with the exception that the gyroplane rotor blades are not twisted.
Twist is used in helicopters to improve hover performance and to delay retreating blade stall.
The gyroplane does not hover, and its exposure to blade stall is much less than for a helicopter. All the gyroplane blades that I know about are untwisted. One advantage is that this makes them somewhat easier to build. However, some negative twist would be beneficial if the disc loading were seven. A readily apparent difference in the distribution of the angle of attack for the same forward speed between gyroplanes and the helicopter mentioned last month is that, in gyroplanes, the high angles of attack on the retreating side are located well inboard.