To my knowledge, no public client shows arrow paths or your combat delta compared to your opponent.
I am really hoping a public client can add these features in.
This video shows what I mean. The client shows your combat delta compared to your opponent so you know if your stronger than them, and it also shows the arrow line when an archer is aiming so that you know not to cross that line.
https://www.youtube.com/watch?v=faSSVtW7OKo&feature=youtu.be