I like electronics, perhaps the 12 yrs as a tech and all the training might sway that. It's not nearly as complicated as you all make it out to be. The systems on the diesels are very simple. I work with F16 electronics, and even to me, those systems are somewhat simple. The newer things are becoming more complex, but that lies mostly with software integration, the electronic side of things is still not that complex.
Is it the lack of experience that makes you "hate" it. Because you certainly cannot question the design, atleast from my perspective you can't. There's several factors when designing a circuit. Face it, lifespan is one of them, they aren't going to pony up the money for that because they won't get the return on it. With people buying new vehicles every few years, why should they bother?