Smooth mouse rotation speed with fine control for aiming?

I have a turret that is controlled with mouse input. The problem is I can't get a balance between rotating fast enough and not losing fine control for aiming at the target. Below is the code. I've experimented with different Lerp speed times, calling from Update, FixedUpdate, LateUpdate etc... nothing has worked.




rayCastFromMouse();

Reference.LookAt(objectivePos);

Quaternion relative = Quaternion.Inverse(bodyRotY.transform.rotation) * Reference.rotation;



//rotation of the second axis
Quaternion objectiveRot = Quaternion.Euler(Reference.rotation.eulerAngles[0] - 110, Reference.eulerAngles[1], 0);
bodyRotZ.transform.rotation = Quaternion.Lerp(bodyRotZ.transform.rotation, objectiveRot, Time.deltaTime * lerpSpeed);


//rotation of the firts axis
objectiveRot = Quaternion.Euler(0, Reference.rotation.eulerAngles[1] - 90, 90); // -90,90
bodyRotY.transform.rotation = Quaternion.Lerp(bodyRotY.transform.rotation, objectiveRot, Time.deltaTime * lerpSpeed);