Furia is a high damage healer mostly for her pyre strike. this can seal kills and stop flankers in their tracks but it takes a long time to spawn just attacking her can bait her to use it and juke her out and seal the kill.
Grover does not exactly counter Kinessa, but can be very annoying to her by simply throwing axes in her general direction, forcing her to constantly reposition, unable to take proper aim.
Your ult is extremely important. you need to do dmg to get it quickly. moral boost and generalized vollys of weapon dmg into the frontline when not in active combat should bring your ult to use very quickly