Wiring harness design

Looking to upgrade electronics on Azzura.
Adding dedicated wiring and upgrading switchpanel for chart plotter, pump, cabin LEDs, external lighting, autopilot and solar panel to existing cabin lighting/radios/nav lighting.
Trying to picture the schematic required to run a day white light/red night light circuits for seperate v-berth reading lights, rear cabin general/nav 'station' and exterior work/relax lights.
Wondering if run a 1-2 run wiring 'spine' fore-aft to split to junction boxes/busbar/switchpanel in aft/mid/fore locatations OR need to run separate circuits back to cabin entrance switchpanel?
I know I need to first write out existing wiring diagram but what is your wiring schematic look like to envisage what to do?
Adding dedicated wiring and upgrading switchpanel for chart plotter, pump, cabin LEDs, external lighting, autopilot and solar panel to existing cabin lighting/radios/nav lighting.
Trying to picture the schematic required to run a day white light/red night light circuits for seperate v-berth reading lights, rear cabin general/nav 'station' and exterior work/relax lights.
Wondering if run a 1-2 run wiring 'spine' fore-aft to split to junction boxes/busbar/switchpanel in aft/mid/fore locatations OR need to run separate circuits back to cabin entrance switchpanel?
I know I need to first write out existing wiring diagram but what is your wiring schematic look like to envisage what to do?