I'm really into designs that are as plain as possible. I used to like all the LEDs and blings when I was younger, but now I'm all about the Scandinavian simplicity.
You don't really need an optical drive nowadays with big, dirt-cheap USB drives and fast internet connections. Absence of front ports could be considered a downside of this case, but on the other hand it's designed to be on your desk and it's so small that I can easily plug anything I want in the back and then take it off again. Not that I even use USB drives frequently anymore.
And when I'm talking about cheaping out on parts, I mean stuff like using a motherboard, PSU or RAM from nameless Chinese manufacturer X, with questionable quality and reliability. Such options aren't really even open to people who build the machines themselves, since self-respecting IT shops don't stock that crap. As for compatibility issues, I'd say that nowadays they are pretty much limited to things like choosing a motherboard and a CPU that have the same socket, which is really easy. I haven't run into the more complicated issues like RAM incompatibility (meaning that the RAM is basically of the right type but just doesn't work with your motherboard) in ages. And like I said, if you don't know which parts to pick yourself, ask the experts!