To enhance single-target effectiveness for a Barbarian, consider incorporating Barbarian retaliation alongside Blood Storm and Dazing Shout in a SC Furyshaper build. Retaliation augments damage output against single targets, although its applicability might be limited to melee weapon attacks unlike Monk's Soul Mirror. In terms of multiclass options, choices like Berserker/Streetfighter could potentially bolster damage output further, while mass interrupt builds might also be advantageous, albeit obtaining the necessary passives in BPM could pose a challenge.
