I'd like a DE/theme that aims to do what the Win2k shell did. File explorer, basic window management, app switching, app launching. Back before every single UI widget had to integrate 47 types of OS feature-of-this-year's-product-cycle functionality.

Chicago95 isn't far off looks-wise. Something slightly more polished than Xfce, but way less than the behemoth that KDE is. I really feel like the modern basic desktop UI was pretty close to complete in 2002-2005, and the moment we tried to make your contacts list available for use in every single application we fell onto a slippery slope from which we have never recovered.