Airconditioning that worked - well. S'pose I could rectify that with a cash injection.
No sunroof; they are trouble - and next to useless in my climate, except on cloudy, mid-winter days or for summer-night cruising. Definitely no good on a sunny day in my part of Oz.
All weather-seal rubbers made from neoprene or some other inorganic, longer-lasting material.
Fully galvanised body.
Automatic shut-off at top and bottom of power-window travel so the regulators don't buckle and fail.
15" wheels.
The "mild" AMG-tuned version of the M110 motor.
Otherwise, I'm perfectly happy with my fairly mechanical (K-Jet, seat adjustments, ventilation, etc.) W116 280SE.
If I wanted a car laden with unreliable electrical gagetry, I could buy any modern car (including a Benz) - but that's not what I want, hence my daily driver being what it is: a garden-variety 116 - only options being the damned sunroof (!), power window cranks, and vacuum central locking.