Q500's - I only jumped on this thread because I couldn't find one directly for the TH480. I have TH480 (Pro).
Q500's - Ouch. Such is the confusion of age. I realized it was not your original thread yesterday, but got caught by it today. That's why it is encouraged to create a new thread for new issues.

At the moment, I suspect the "slow" observation may just be a matter of opinion on your instructor's part. If the standard Yaw rate and expo are appropriate for YOUR needs, I would leave them as is.