DIY Laptop

I just bought a laptop. I must have spent six hours researching what laptop to buy, and more specifically what I wanted in it. Eventually, I compromised. I got the memory, processor, and video card I wanted, but couldn't get my favored hard drive. In fact, no laptop was available with everything I wanted. Sure, Dell allows you to "build" your own, but even their options are limited to their opinions of what should or shouldn't be offered.
I've never had this problem with desktops. The simple reason is that I always build my desktops. But I can't build my laptop.
Why? Because laptop cases are designed to be as portable as possible, which means designing the case around the components, rather than allowing room for the small intricacies of the laptop.

So picture this...
A standard laptop case. You buy the case and battery, and then you build in all of your accessories seperately. Sure, the case will have to be a smidge bigger, but all laptops, even the largest, are all roughly the same size. And why not offer different sizes? It makes sense that the case size would differ based upon the size of screen, so offer a light version that can only handle certain sizes, and a heavy version that could handle whatever laptop component you could jam into it.
Getting a motherboard manufacturer to fit each case shouldn't be a problem (every laptop manufacturer does it), and after the first you'll start seeing others design to the same specifications to remain competitive. Even if they don't, you still have your one motherboard selection.
I'm sure there are plenty of reasons this wouldn't work, but plenty of reasons why it would (most of which start with the letter '$'). Perhaps its time somebody open the market to what the consumer wants, not what the manufacturer can force them to buy.