I mean, those UI's are nice looking, but it doesn't really seem like they show any information.
My Portrait and the enemy portrait are supposed to be just below the center of the screen but their position kept randomly resetting during the latest Stress Test, but besides that this is my probably hilarious UI. Based heavily off of the UI I used on the modern game (with additions such as the swing timer), i've just grown to love it over time.
As you can see, i'm not much of a simple-UI lover, I love having information on my screen. And I love the style of Default. That tough jerky and refreshing spring water on my main action bar is a mistake, I musta not noticed them. I use a Logitech g600 with it's ring finger button bound to Left-Shift, so that's how I use all those buttons on that action bar.
EDIT: Details would normally be stretched upwards to fit snug right there, I set up my UI before I got my pet then forgot to fix it up
When I get home I'll post a picture of mine in Legion doing Heroic/Mythic Antorus with my xbox controller and the interface looked similar to yours. Little to no information at all, maybe Recount! And that's it. not even boss/player frames. (And I always top the metters 1-3 dpsing).
I mean, those UI's are nice looking, but it doesn't really seem like they show any information.
The colored bars are party health, which grow upward as more people join/raids are made. Bottom two bars are my health/targets health. Buffs in top right, debuffs appear bottom center to the left. Chat bottom left, which fades out over time. Cast bar is the grey bar. DPS/Healing chart, minimap, and player names are toggled on keybind. Most of the time don't need to see those. What more information is needed?
My UI is on my signature. It's basically Blizzard UI, but with some tweaks and a lot of options.
Don't have a picture of mine because I was not in beta, but I've always been a bit of a purist. I just keep the default blizz ui with a couple essential addons, like DruidBar.
I couldn't find any picture of me doing mythics, weird... but I have this video that I've made on how to configure ConsolePort. Near the end of the video you can see my UI doing a normal Antorus run. Later in the expansion I did some tweaks.
https://www.youtube.com/watch?v=PQVz4jhNI0s&feature=youtu.be
On the top of my head these are the addons I've been running for a long time. There is some in game commands you have to do to pretty it up. It's not default like that. And yes this is on a private server. Im going to try and replicate it the best I can though.
LazyPig
Ace 2
Atlas
AtlasLoot Enhanced
Attack bar timer
Bagnon
BananaBar Raid Symbols
Banknon
Bartender2 Dreamlayout
Big Wigs Elysium
Buffalo
cartographer
classic Snowfall
Improved Error Frame
KLHThreatMeter
Luna Unit Frames
maff
Miks scrolling battle text
MiniCoords
MobHealth3
oCB3
Omni Cooldown Count
Outfitter
pallypower
postal
TheoryCraft
TomTom
TrinektMenu
VQueue
Xloot
FonTabulous
BuffBlock
SW_Stats
Simple Mini map
MoveAnything!