The KDE guys have been on fire for the past two years. Between their theming, color selection, and session handling they've come a long ways. They've also implemented some gnome-only features such as the overview, albeit in a very optional way. As opposed to eliminating a panel and forcing you to use the overview to see what applications or windows you have open, or available to launch, it's just a window management tool instead of a UX paradigm.

Their wayland session is stable and also deals with xwayland in a very different way. If you set a custom scaling factor, the QT apps and GTK apps are talked to in a way that makes the same scaling factor consistent across all your applications, even under a wayland session with xwayland. The Gnome devs hand-wring about how the world has to be perfect before implementing an idea, where the KDE devs try something and then iterate if it's successful.