Why doesn’t the option to have an auto-throttle system for Cirrus aircrafts exist ?
The device would be simple, select the IAS speed with a knob near the airspeed indicator, have an engage & disengaged button located on the throttle lever. When engaged you could put your hand lightly on the throttle lever and feel the changes the auto-throttle system is doing and at the same time override it by forcing against the servo motor (emergency only) or press the disengaged button to take over the throttle control. Seems to me to be a less complex setup then the autopilot system that exists in the SR2x today.
The reason why I bring it up is I think it would be a welcomed safety feature for both the novice and experienced pilot. Novice pilots seem to have trouble with keeping the correct approach speeds while at the same time keeping the proper decent angle. (especially when they are flying into an unfamiliar airport) A more experienced IFR pilot in IMC conditions performing a VOR approach with multiple step downs, often has trouble keeping the a constant airspeed because all other things that is in his/her scan at the time.
Of course, the auto-throttle system would be labeled to say stuff like “Not for use during take-offs” and maybe cruise flight, but for any kind of approaches, it seems to me that this would help reduce pilot workload, and hence make the plane easier and safer to fly.