I've said it before, and I'll say it again - Deepin is second to none, as far as user interfaces go. It is one of only three environments I'd suggest to someone, whether newbie or pro. It is probably the only one I'd consider teaching; Budgie is essentially Deepin's efficient mode, but uglier, while Cinnamon is yesterday's news.
The system apps have a relatively unified and beautiful design language, which in the Unix world is essentially unheard of. Elementary is even more unified, but its design has gone counter to Unix consensus, which means that its integrated applications clash.
Just open the System Monitor on Deepin to see what I mean. It looks like it's from 2018. Even the Windows 10 task manager isn't as beautiful, and its predecessor (Win8 and earlier) was from 1997! (Literally, the WinNT 4 taskman.exe) Firefox next to it looks fine - the widgets are similar, etc. HexChat and Pamac look fairly ugly in Deepin - well, Pamac looks ugly on anything, but still, no Betty.
The integrated apps also add some measure of utility. I install Spacemacs on all my systems, just because I'm used to Vi keys and Lisp, but I could use the Deepin editor in a pinch. There's a graphically beautiful backup utility, and functional as well. There's an Exposé-alike (though I've so far been unable to map it to ALT/Tab as I would like).
And, the terminal. Oh, wow. Best damn terminal I've ever used in my life. The closest second would be Tilix, but I've never had a distro where ALT/F2 automatically invokes a Quake-alike Tilix session from the top of the screen. Manjaro-Deepin does it, with the Deepin terminal. It does tile mode. It does tabs. It does transparency---with blur!
All right, KDE Plasma could be configured to act to my liking. Maybe even more than Deepin - but I want an environment that works fine the first time. Literally the only things I have had to customise, for the Deepin Desktop Environment, were the desktop wallpaper (Oh God that ugly shade of blue) and the font size (way too small on my MacBook Pro!)
Manjaro Deepin is probably the only system that I could get to work on a bare installation, using just the system apps. Back when I used Ubuntu with Budgie and Cinnamon, my apt-get list, for getting the system into a usable state, was two pages long. On this, I've only really had to install five or six packages (off the top of my head, Wine, LaTeX, Emacs, Inkscape, Spotify, Lynx for getting past paywalls on my morning paper, and, erm, that's it, I think).
The only thing Deepin really fails on is documentation. All right, the package manager is ugly and could do with a replacement, and bloody Irssi would be an improvement over HexChat (it's a text-mode client, and it looks better, FFS!) But those are niggling issues, irritations rather than deal-breakers. First-world problems.
Documentation, on the other hand, doesn't mention certain crucial facts. For example, it talks about the terminal's "Quake mode", but doesn't specify how to activate it! It doesn't say how you can get a mini-Exposé, for easier task switching (just hover over the app's taskbar icon). There are... "interestiing" uses of the English language, but I can forgive those, given that English isn't an official language in China.
All in all, 9/10! A solid effort, with only minor issues. Looks and works better than Windows 10, which I would say is the most solid-looking graphical environment out there (leaves OS X in the dust!)