Because Torvald can no longer drain shields your ability to specifically counter him has been significantly decreased. However, you have Nullify on your side, as well as a decent DPS - don't hesitate to fight fire with fire and get into close combat.
Recently, Maeve's Midnight was heavily nerfed - it can be countered by Resilience (at the time of making this) and go down to a minimum duration of around 2 seconds. If the option is available to you, buy Resilience - especially if you're her target.
While I generally recommend Agony in the event a Ruckus is present, if you find yourself alone against a Ruckus at full health then that small time won't be nearly enough to kill him. Just shoot him, Rend Soul, and use the stun time to get out.
Whenever you're up against a Maeve, your Fireball will be necessary as Maeve is more than able to kill you from a distance. If you're alone with a Maeve and not at low health, you can put up your shield and retreat, or burn her with the fireballs.
Sha Lin is the ultimate way of telling you to get out of the sky - and when you're on the ground, Impaler Arrow is a huge threat for you. Resilience will be necessary; a good Sha Lin will deal too much damage for Haven to be effective.