The most noticeable thing that needs to be fixed is the fact that skills dont always activate when you want them to. It's always random when it happens but it can be infuriating in a situation where you need your skills to activate. Either a dash, or a skill that blocks a certain attack. These can't be used effectively if they dont activate when you need them to. It happens when melee skills, ranged skills, hell...even heals have had ticks where they dont do anything.
And no this isn't the case of being "confused" or a status effect that causes your skills to not activate. Its just a random thing, and moving your character anywhere can fix it...but in the middle of combat, the last thing you want to find out is AFTER you needed to use the skill. So, combat wise...this is a fix that needs to be figured out and fixed if they want to say their combat has been smoothed out.