Hey great add-on. I do have a small suggestion. Is it possible to add a functionality to solo the selected rig -- meaning it hides all other rigs in the list(rigs only not meshes) when you select one. The visual clutter of working with multiple characters with complex rigs like rigify could really use a function like this. You could select whether it centers, solos, or both via toggles. Anyway, thanks for this addon.
This is a nice, simple and useful addon. Unfortunately, I get a python error when trying to switch the rig in Pose mode. Since this addon works specifically with armatures, I believe it should be able to handle this. Besides, Python errors are not a good result in general. :) 4 stars because of that, I'd be happy to update my rating to 5 if this gets fixed.