If you've experienced the drudgery of slow retargeting workflows, you'll want this tool!

Retarget Helper lets you quickly bind motion data from one object/armature to another object/armature, with just a few mouse clicks. Quickly build a map of position/rotation/scale constraints, either with an automated tool which matches similar names, or manually with a curated GUI. 

Supports mapping to/from both objects and armature bones. Drop in objects into the respective fields and the tool scans both their outliner hierarchy, and contained armatures.

After mapping is complete, push the constraints with a single button, and clear them out just as easily if something got messed up.