As for this app, not sure I understand the utility of putting anything useful on the lowest layer of your desktop where it's going to immediately be covered up with windows.
I am the exact opposite.
Having things embedded into the desktop works for me as I use the desktop and do not have apps full screen unless they need that space. I drag textclippings to the desktop, keep files on it for things I currently want to access quickly, and pressing F11 means I quickly view everything in just the same way as pressing F12 made Dashboard appear. When I am not using an app I hide it rather than let them stack one atop the other.
But I never used Dashboard as it made no sense to me. If you want to make a calculator appear over other windows, just use the calculator app etc. It felt cluttered having to have a number of superfluous extra windows appear all over the screen when I just wanted to see the weather. Dashboard is all or nothing when I only ever want one thing at a time. It is easier for me to use apps.
Embedded widgets allows me to quickly see information presented in an way that blends into the background, avoiding the clutter of windows which being autistic I find uncomfortable. I can focus on what I want and the rest becomes no part of the desktop itself.
(Also I used to use Quicksilver just so I could assign F-key hotkeys to Applescripts that could open then toggle the hidden state of applications I wanted to quickly access anyway. It was great until Apple added all its Gatekeeper features that made them practically unsuable. Now they take a couple of seconds after running to act, which I know it was not Quicksilver as it is the same whe running them from the AppleScript menu. So now I have to Cmd+Tab / Cmd+H)
I currently use Übersicht to present a panel of widgets on the left edge of my screen to show information in a place that is often left uncovered when doing simple things like web browsing, email, or Pages. And when I want to do something full screen, such as photo editing, I rarely need that sort of extra information anyway. And if I do, I can just toggle access with F11 or the bottom right hot corner.