What "critical design aspects"? People are used to seeing a cluttered grid of unnecessary things. Look at any website, and it could be easily rearranged into something like this, with very few elements. It would look much better, be easier to use, and load faster.
Can you tell me exactly what that design is missing, and why what's "missing" needs to be there?
I can't tell you what it's missing because I don't know what you were trying to design and I usually charge for that anyways ;)
I can tell you what you overlooked. For some reason you've settled on a whopping 30px padding throughout but despite all that space, the content still looks squished together. To fix that eyesore rather than add space around the content, increase the font-size, line, and letter spacing to improve readability.
While you're at it, ditch the drop shadow. You've done an awful job of implementing it because it exceeds your content width and doesn't blend in well. Frankly it would look more "minimal" without it, but that's what you're shooting for, right? The header is also abnormally sized at 108px tall, it may just be 2px off (or 8) but it's picking up on the small things that make a good designer.