I think it helps controller users add more skills into their controller without taking up room of their buttons.

For Keyboard-Mouse, I don't think it helps as much.

As a Slayer, it basically means that I don't have to bind Overhand Strike. Only time I ever use it is when it's available as a spacebar skill.

Also, I won't have to bind Throat Slash when that comes out either.

My slayer got to max level with left click and space bar.
It's pretty OP for slayers.