I'd rather they give everyone their own LB gauge and give you a buff on use (split from damage normal LB would do), like 25% extra damage for 10s, maybe have a power-up animation. As stated by OP current iteration is pointless for majority of classes outside of melee, considering a vast majority of raids/alliance raids are a single boss.

Alternatively they could just give 3 variations, one for single target, multi targets, AoE. Same for healers, maybe a shield buff, large HoT, mass rez. Having extra animations would be cool to see.