(Controller / M&K?) Highlight already set abilities

When assigning skills or similar, on Controller at least, it'd be UI wise easier to see what is already set with what button.

Below, you see the current system:
https://imgur.com/a/cYfvavW

Here you see what I propose, with an example for A X Y B:
https://imgur.com/a/qnVDVfX

I think it'd be easier to recognize immediately what is where, and would see it as a great improvement in visual clarity.