Hi Martin, I think this needs more in-depth investigation. We've had a couple of, I'd say, knee jerk shortcuts pushed to master without much thought about them (Alt+Space for KRunner, Meta+number for tasks).
>From my point of view, window switching, present windows and the desktop grid are essentially the same thing. The best solution IMO would be to combine them all, and the UI should not be the same for all devices. For example, on a medium screen, for devices that are handheld, window switcher is perfect since the window list is reachable with the finger the user swiped with. For small screens, that is on the phones, the whole screens should be coverable by 'the finger', so a whole screen could be used for the switching (like present windows). On larger devices that are not handhelds, but are still touch-enabled, we could have a desktop grid, or some present windows + present virtual desktops switcher. Cheers, Ivan