I have updated a plugin to add a new function.

Now the user is able to create layer  selecting specific bones.

After selecting your grease pencil and your armature from the "set Objects" panel. Go to pose mode and select the bones you want to create grease pencil layer with, then hit "Create layers selected by bones" to have your new made layer already linked to designated bones. 

Makes for a less of a clutter overall on your grease pencil object.