I want to present my full rig for humanoid character. I also created a simple tools for things like: FK/IK snap, retarget animations, space switching and selecting controls. Although I have just started my journay with scripting I do think that this is an essential part of rigging and even just some simple scripts can have a dramatic effect on your workflow.
basic functions one by one
fk/ik snap
space switching
retarget anim from UE4_mannequin
retarget anim from mixamo