What electronics would you remove from modern cars?

I'm having such a difficult time replacing my oil filter housing at the moment, and had probably accidently dropped something down the cylinder head (won't truly know until I crank that car), so at this point I'm at the acceptance phase of death. So I'm just joking around with myself and thinking of remodeling the engine bay in the future as a project, which came with the question "should I add all the electronics that modern engines have" probably not, just the ones that may help with diagnostics.
Also, what's an example of a sedan that is prime example of longevity, and what are the detail of that, i.e. why does it last that long; why aren't all cars reliable? (besides the money part), quality parts, horrible engineering, etc.
One thing I'll remove from the engine is A/C, I can live without it, but will probably add little holes for hot air to get out. But that could lower MPG.

Sincerely,
Juan