I have noticed that when I am chasing someone, my effective melee range seems to shrink to almost nothing. Right now, when I want to land hits consistently on someone running away from me, I am having to place my character essentially inside of theirs.
I know this is not intended because when we are standing still I can be some units away and still land hits.
Perhaps there is a minor latency issue with movement and checking where everyone is at? I think this could be resolved by extending melee range 50-100 units or so if 1 or both players are moving.