Easy to use (rotation) +
good survivability +
good damage +
versatility (mobs + champs + bounty) +
not expensive to equip +
condi_cleans/reflecting_projectiles/stability (highly desirable capabilities with bosses fighting) in a single build = Condi Mirage | Staff
Once again, I not say that it is the best build in general (say, Renegade will be more damaging prof), I say instead that from my point of view this is the simplest from strongest one.
The other two safe and strong options are Herald and Scourge, but I think they have a little bit more complex rotation and, the main - they have not reflecting_projectiles abilities.
Other options (say Renegade, or Firebrand, or ...) will be more complex and are more demanding on getting the best result.