really big mod-list you have here
Would be nice to see some pictures, how your modifications changed aero.
Some mod seems hair-splitting to me though.
I mean these:
* remove cluster useless indicator lights
* removed all but driver side door lights
* usually drive with only parkers on at night rather than full lights. Still visible to other drivers
* Disconnected rear center break light. Not required as already 2 rear break lights
* Disconnected side indicator lights
door lights, braking lights are not turned on normally, so let them be
You are reducing safety.
Replacing all lights to LEDs is better. You can find many led bulbs in ebay cheap.
One idea - you could add MPGuino instrumentation to get real-time feedback.
Are you pulse-and-gliding?