Really trying hard to not sound biased here, but I have a feeling starting off with this, is not gonna help it:

Compared to Cinnamon, KDE is pretty much better at everything. It's a thousand times more configurable, it's more feature-rich and the default applications are more powerful. The search in KDE, called KRunner, is also something that many people love.

Where Cinnamon is better:

- Not making your eyes bleed over when you look at the settings screen (because KDE really has a lot of settings).

- Less incompatible options. In KDE, you sometimes dick around with one setting and it invalidates another setting. (Usually nothing important, though.)

- Less features usually means less confusion for less technically inclined users.

- Its keyboard shortcuts are quite similar to those of Windows. KDE deviates in places from that.

- It uses probably like 100 MB less RAM and presumably a few less CPU cycles. (In the default configuration, that is.)

- It's somewhat more stable. KDE has gotten a lot better at this over the last couple of releases, but it's still not yet quite as rock-solid and probably won't ever be.

- Cinnamon is better at being Cinnamon. In KDE, with how configurable it is, you can rebuild most desktop environments in it and Cinnamon is very similar to the KDE default, too. But if all you want is exactly Cinnamon, then just using Cinnamon is cleaner.

As for Awesome:

+ It's a lot lighter than KDE.

+ It works better independent from the distro. I don't think there's any distro where Awesome is not good. With KDE, I'd consider openSUSE, Manjaro and KDE Neon good. Fedora and Debian are not terrible. Ubuntu is often garbage.

+ There's some keyboard shortcut in Awesome to unminimize windows in reverse order of how you minimized them, which I was quite fond of.

+ It has tiling.

There's some scripts that you can use in KDE to also make it tile its windows, but those are more limited than the tiling you have in Awesome. They are also somewhat laggy and sometimes just bug out.

You can use bspwm or i3 inside of KDE, which is also somewhat hacky, but it does work well enough that I use KDE+bspwm as my daily setup. If you want a quick guide on that, let me know.

Benefits of using KDE over Awesome:

- KDE has lots of smaller and bigger features that Awesome doesn't have. I for example do some webdev, so I have a color picker widget in my panel. I could live without it, but I'd also just rather not. And again, the search of KDE is just really good. Awesome doesn't have anything like that.

- Again, the KDE default applications are really good. Having those preinstalled rather than needing to hunt everything down yourself is worth something. And even if you don't end up using the desktop environment, lots of these applications are considered best-in-class by many people, so you could end up incorporating them into your Awesome workflow.

- The KDE applications + the desktop environment also form a whole. They work well with one another, work similar to another and are thoroughly tested on that desktop environment.

- KDE is a desktop environment, not just a window manager. So, it can handle volume, notifications, screen brightness, power management, connectivity etc.. With Awesome, you need your own custom solutions for many things.

- Partially as a result of that, KDE is also more compatible with the outside world. Quickly hooking up a second monitor or a projector to Awesome is not necessarily something I'd feel confident about. And just in general more of these sort of edge cases are tested against and implemented in KDE, because the user base is much bigger.