I would ask you to reconsider the implementation of a gyro only mode. As many have stated in this forum, the compass on most devices is poor at best. I believe the iPhone's compass normally gets an accuracy of around 10-12 degrees, even after calibration. The gyro, on the other hand is very accurate, and using the relative attitude produced by CMDeviceMotion (on iPhone) can be accurate to less than a degree.
Having a gyro only mode would effectively allow Sky Safari to become a simple Push-To tool. Mounting the phone on the telescope, pointing at a known bright object, and turning on the gyro would allow push-to searches, especially over short angular distances. On the other hand with the compass-fusion mode, that becomes impossible since the compass always has an error of a few degrees, even after calibration.
I hope you can reconsider the decision that a separate "gyro button is not coming back". I realize this may compete against the fancier go-to setups that Sky Safari supports, but for many of us it would be a great addition.