Rather than a UI that's changed to whether the majority likes it or not, why not just have it be adjustable and lockable depending on the player?
Just add a UI option in the options, and have it movable or lockable.

Honestly there were parts of the old UI that I liked, and parts in the new UI that I like..

For example: the shield bar is too fat in my opinion, but I like the fact that it's there, so I wanna adjust it's size. So adjustable HP and Shield bars..
Or have it possible for me to have a 50/50 HP/Shield bar that goes up the perimeter of my character's image. The option of putting the status and health bars where we want would also be nice.

I'm not sure if I'm the only one but I would like to adjust transparency to the weapon visuals when I scroll up or down. Changing weapons shouldn't be such a pain that it impairs my vision in combat.

I liked some of the previous menu options but the current location for where you need to click on them is opposite now. This should be adjustable too.

To any other player who reads this, Give your own opinion on what UI you want to be Customizable.