A remarkable feature would be the different colored arrows. Instead of drawing everything in yellow, which can be messy and confusing after marking up a few moves, adding different colors would help keep it much more retainable and organized.
That's already possible with holding different keys when drawing the arrows.
https://support.chess.com/article/702-how-can-i-draw-arrows-on-the-board-like-streamers-do
A remarkable feature would be the different colored arrows. Instead of drawing everything in yellow, which can be messy and confusing after marking up a few moves, adding different colors would help keep it much more retainable and organized.