Linux

I run tiny core linux for the UI personally

Probably any distro that ships KDE Plasma 5 as default - I'm stuck with GNOME for now as I need to use Evolution for work (EWS mail accounts), but if I had the choice I'd probably be on Plasma.

I use KDE Plasma on RebornOS (an arch spin).

You can use most desktop environments on most distros.

If a distro has its own GUI and it doesn't exist on other distros, usually that means either it isn't free software or it's not good enough that anyone has bothered to package it for other distros.

Fedora with Gnome

Distro? Probably Debian, because it has all the desktop environments. If you want, you can have Plasma, Gnome, Xfce, Cinnamon, and MATE all installed at the same time and switch between them at will. Most distros seem focused on one specific DE, which if I'm not mistaken means switching to another involves reinstalling the whole operating system.

The big downside of Debian is that the software in it tends to be very out of date. You'll get security updates and the occasional bug fix between Debian releases, but that's about all you'll get.

You can get a rolling-release experience by running the “unstable” version, but as the name implies, upgrades will sometimes fail or break something, and you need to know your way around the system in order to recover from that. Not a problem if you want to learn to be a Linux sysadmin anyway, but if you want your system to Just Work™, then unstable Debian is unfortunately not for you. It's a trade-off, as with most things in life.

I kept wanting to try the new GNOME, but it kept failing me on fundamentals - I.e, refusing to rebind certain keys, constantly failing plugins (such as the one to merge window title bars with the topbar), and bugs gallore.

So for years, I was a GNOME 2->KDE refugees, with only minimal complaints. KDE is nice.

But now it seems GNOME has finally stabilized and conceded enough to user wishes that it's useful again. And with those things done, I'm now quite enjoying it.

Just trying out OpenSuse microOS currently, as an alternative to Fedora Kinoite, and the installer doesnt even load.

I dont like Ubuntus variant of Gnome. I think GNOME can look good but its apps are often horrible. Mint has a better set of simple but powerful tools.

But I would stay with anything rocking KDE. I recommend fedora Kinoite fro ublue.it (better video previews and working RPM firefox basically), its a really great distro.

Deepin is great too. Unfortunately it is not fully translated so that you come across Chinese quite often.

The real question is what Window Manager has the best GUI... you can run any window manager on any distro - it just takes a little work.

If you're talking about out-of-the-box without any user customization, I'll make a couple suggestions that I think work for new Linux users - not that I'm saying you're green, but most power users know they can fully design the OS from the ground up if needed.

PopOS - In between - GNOME-like with some PopOS customizations under the hood.

ElementaryOS - MacOS-like WM thats clean fresh and easy to understand

Mint - Cinnamon DM, Windows-like with some customization possible

For me, it's Fedora + KDE when I need a GUI. I used to be an AwesomeWM guy for a very long time but I needed a proper GUI for my 5 year old. I'll convert her to i3 or Awesome one day....

The distro which comes with the best customization in my opinion is Pop!_OS. Simple, clean, straightforward and comes with the POP SHELL which basically simulates a tiling window manager