Chances are, this will probably fall on me to address, but I am documenting it here in case someone else realizes the issue.

When creating 3d axes in the old manner (ie, ax = Axes3D(fig)), the panning and zooming features are completely useless and often produces incomprehensible results. Axes created in the newer manner (ie, ax = fig.gca(projection='3d')) has somewhat better behavior, but still quite useless.

While pan and zoom has never really been properly supported in mplot3d, the current behavior is significantly worse than before. I suspect that there might be some interactions with a variety of changes. First, there were some changes to figure object itself, which may have not been properly tested with non-subplotted axes (which would explain differences in behavior between the old style and new style). Second, I suspect that some changes to the clipping logic for Agg might be causing some of the issues with zooming and panning.

I think I will temporarily address this issue by disabling pan and zoom for Axes3D objects. I also want to make the Home button capable of returning the figure view back to normal. It does not appear to do this right now.