This sampler kit is a great idea. I would have skipped the MX black keyboard if I had tested; MX Brown is closest to that old IBM feel. I'm still debating buying O-rings for one or more of my keyboards. Maybe buy one set and use it just for the typing-key subset.
As far as aluminum goes, there is no functional advantage to it. It's only for looks. It's for the special machine you built in a Lian Li case that stayed (or will stay) a favorite long past Ivy, Haswell, whatever ... And it is absolutely unique. Yes you can program an EDM machine to carve a top shell out of aluminum, titanium, wood veneers ... but there's only one Year of the Snake edition,
Aside from the long-term collector's view, you might also consider "rewarding" Ducky for producing an artisan product!
Finally, look at the future of computing. Maybe we'll be using touch screens, but I doubt it. We're far more likely to have iimited hand gesturing like the Xbox Kinect. However, there's a problem adding another device to most desktops, and so this means the product is going to have to attach, either to the monitor or to the keyboard. A Ducky keyboard can be designed "tenkeyless" and have sufficient physical real estate to hold one or two cameras plus a gyroscope, maybe sensors to detect metal finger rings for a 3D input.
All this can be helped by your keyboard selection today, and your decision to help make Ducky a more prosperous company.