Looking through some tuts on Youtube I’ve mostly seen extra bones being used as controls. I’ve come from Modo where settings empties for bone control. If I use the same Armature with control bones attached I still see all the bones of the rig and is quite messy. What’s the best practice for controls ?
Those control bones are meant to avoid old dependency graph (blender 2.8 will have a new one) dependency cycles. To keep your self organize i will advise you make use of bones layers. So control bones in 1 layer, def bones on an other and mechanic bones on another so just toggle visibility when you want to see specific layer.
Hope this helped 
Great, thanks.