You could use the
Engine event handler to run a script whenever the engine is turned on. Maybe limit it be distance from the base so that restarts in the field won't break, or not!
Not sure about changing the HUD color or did you mean just assigning random damage and fixing it for the effect?
The first steps I guess would be to find which items can be damaged on each vehicle and decide how likely you want those to fail.
Take On Helicopters has a really nice preflight check and repair system. I wonder if we'll get that in ArmA3?