Most people who manipulate 3D scatterplots do not want to rotate about the Z axis, and they end up struggling to keep it 'right side up' after a few rotations. Make the mouse movement work like the 'Move and Rotate' behavior in the animated gif below.
Here is an add-in that provide the functionality in the animation above:
Provide an option to lock the z axis, enable it by default. When enabled, horizontal movement of the mouse rotates the chart about the y axis, no matter where the user initially clicked on the chart. Vertical movement rotates the chart about the x axis.