Yes, I used Hagbane once to “rescue” a friend on Trail of Treachery Cata from an assassin amidst black rats and plague monks; it killed the assassin, the black rats, the plague monks, and my friend in just about 3 charged shots. Not unlike the Battle Wizards correction, it’s another area DOT weapon that excels at high-density amounts of tough enemies like on Cata; it’s easy to get the most damage dealt with AOE DOT.
Maybe Waystalker non-piercing shot ults in effect are not that OP, so much as it boring and lacking the effort on the player’s part.
The thing that is arguably a bit OP is all the cooldown she has access to 30% + 5% every 10 seconds is a bit extreme much for an ult that doesn’t really require the player to do much. 30% takes it to from 80 to 56 seconds; every 10 seconds takes off 5% which is 4 seconds for every 10 making it effectively every 40 seconds and I’ve timed it at 28 seconds in a crowd. Then just throw in a petty personality chasing kills and spamming javelins with a bunch of ult cooldown, and you get the picture. It may be that the Waystalker is noob-friendly DPS more than she is extremely powerful.