Here's a simple addon I just wrote for Blender. It automatically generates a panel in the Properties shelf for toggling visibility for the layers of a rig. Previously this required a custom python script for each character, but by using this addon you can have a panel simply by adding some extra properties to your rig.
Firstly, download and install it from here:
(copy and paste it into a new text file, save it as "autoRigLayers.py", then install and enable it in Blender via the user prefs)
Now all you have to do is prepare your rig...
- Make a property called "autoRigLayers" and set its value to "1"
- Make a property called "layer.1" and set its value to the appropriate layer name.
- Repeat step 2 for all the rig layers that you want to appear on the panel
Optionally you can set the number of columns in the panel. This is done by adding property called "layer.cols" and setting its value to a whole number.
Hope this is useful to you. Let me know in the comments below if you find any major bugs.