The level of responsibility the assemblers have must be very high. It's like assembling multiple spacecraft, really. One loose wire and you kill a lot of people.
There's a bit of redundancy to make sure that doesn't happen.
Sadly, with aerospace stuff, there actually hasn't been that much new stuff in a few decades. Few people have mentioned the SR-71. Heck, it still holds records from 30 odd years ago. Unfortunately there's been very little work to make modern aircrafts faster. Nowadays it's all about fuel efficiency i.e. lower drag, lighter materials, better control surfaces etc.
Heck, there's more search on making planes quieter than making them faster.
Not saying there's anything wrong with the approach but the 70s was really the heyday of aerospace. We need another good cold war to get moving again.