Pedrolif, hope it doesn't seem like we're ganging up on you, but I really don't think you'll get much of a reception from the Big 3. You'll probably get a polite but generic form letter from the company, and if you're lucky, a few bumper stickers or T-Shirts.
However, I totally agree with you in terms of service items being hard to get to. But that's not just within the last 5 years. That's been decades in the making. Whenever I look at a mid-late '90s F-Body, the main thought on my mind is "Man, those rear spark plugs must be a nightmare to get to!" It seems like the best way is to put it on a lift and get them from underneath, assuming you have one of those at home. Yeah, engineers make some weird decisions on where to put things sometimes. I do think the OEs could be more attuned to feedback from technicians and repair guys. Even with more modern cars, some are a "piece of cake" to work on, whereas others are a total "pain in the @$$."
I think your best bet would be to make an appeal to make the vehicles more serviceable. They might listen to that. However, playing devil's advocate, the more complicated they make them to service, the greater the profit center is for the dealership in terms of billable hours. So...Who knows. Anyway, good luck.