The new engine helped me with the actual in game performance within the matches, that is the only upside.

I think the problems with the new menus can be shown with how they fixed the problems with the trait menu:
The trait menu previously had very little space, and was cluttered with big icons and very little information.
You needed to scroll multiple screens to see all the traits at once, and it felt "zoomed in" and cluttered.
They fixed this by reducing the size of the icons and added a showcase part in the middle of the screen. Thereby making it feel like picking from a box of many, instead of having to search through a giant catalog.
The other menus have taken the opposite course, bigger buttons, less information, and more scrolling/flipping through pages to get to where you want.

The engine performance is a step forward, but the giant leap backwards in experience otherwise, is detrimental to the enjoyment of this game.

The new engine helped me with the actual in game performance within the matches, that is the only upside. I think the problems with the new menus can be shown with how they fixed the problems with the trait menu: The trait menu previously had very little space, and was cluttered with big icons and very little information. You needed to scroll multiple screens to see all the traits at once, and it felt "zoomed in" and cluttered. They fixed this by reducing the size of the icons and added a showcase part in the middle of the screen. Thereby making it feel like picking from a box of many, instead of having to search through a giant catalog. The other menus have taken the opposite course, bigger buttons, less information, and more scrolling/flipping through pages to get to where you want. The engine performance is a step forward, but the giant leap backwards in experience otherwise, is detrimental to the enjoyment of this game.