I notice that the current default Plasma layout has no "Show Desktop" widget by default -- this could be added in the bottom-right corner for consistency with Microsoft Windows.

Additionally, I find it annoying that the default action for moving the mouse to the top-left corner is "Present Windows" -- I find that this interferes with applications sometimes and their top-left menu. I move this also to be in the bottom-right corner and find that it works logically well together with the "Show Desktop" widget.

"Show Desktop" in my setup if I move my pointer to the bottom-right:


"Present windows" in my setup if I push my pointer further into the corner:


This works well, though perhaps for simplicity these could also be combined into a single function? Maybe have a "Present windows" widget where clicking on the desktop backround also shows the desktop. Maybe this could also be similar to the Windows 10 Task View whereby you can also add multiple desktops from one interface.

One other issue is that the Panel settings icon is by default in the bottom-right (though this hides when you lock the widgets). I don't think this is a good design, and confuses new users. Better would just be a right-click "Customize mode" option on the panel and on the desktop instead. Widgets would always be locked by default and only unlocked when in Customize mode. This could be made to be something like the Customize mode that comes with Firefox.

I agree widget should be locked by default, but that's a poweruser's opinion.

If you want a show desktop widget that looks exactly like Window's try the downloadable Win7 Show Desktop widget (https://store.kde.org/p/1100895/). It removes the icon and overlays the panel's top/right/bottom margins so you can flick right to the corner.