question on bulkhead connector bypass

I'm on a mission to learn more about this overall system and any mods that can improve it short of replacing the harnesses. Looking at all the diagrams is one thing but understanding how factory intended it to work is something else. Right now I'm thinking why did one side of VR go to ignition circuit? could it have gone elsewhere for the purpose that terminal served. IS going direct to the positive battery post essentially the same thing. I appreciate the knowledgeable people here who sorta stick their necks out a little answering questions, as there are often some differing opinions ,or at least more than one way to skin a cat..