Making me a wiring diagram

Hey guys,
Been hot as heck here and the garage has been sitting at a low of 200 degrees so, instead of sweating to death, I've been hiding in my cool living room and playing super nerd on my computer :) So, I've been trying to create the ultimate wiring diagram and figured I'd get y'alls input on where to go with it from here.
What I've done so far is take the wiring diagram I have and have recreated it using a graphics program. I put all the wires in color and have all the wire colors, equipment, etc. separated out by layer so I can call up a section of the diagram without having to deal with the full spaghetti of the complete wiring diagram. What I would like to do next is separate out the systems so, for example, if I was working on a bad headlight, I could have just the lighting circuit showing. I am kinda stuck on what systems I should put on it. So far I thought front lighting, rear lighting, ignition, and gauges/dash. Anyone have any thoughts/ideas?