Ingo Clemens from Brave Rabbit has a look at all the new features that are offered in the latest version of SHAPES, a tool that brings blend shape editing to the forefront in Maya.
The plugin brings compatibility with Maya 2017, as well as other massive updates. Only a little while ago, the tool added a new Weight Driver RBF mode making it possible to interpolate multiple shapes for each driving node.
There is also new support for the Maya pose interpolator for Maya 2016.5 and later. Have a look at working with the pose interpolator, and a short vid that describes the differences between the weight driver working in RBF mode and the pose interpolator, and
SHAPES for Maya has become the go-to tool for rigging and technical artists because of its simplicity and vast capabilities. If you are a registered user, all updates are free.