And a5s. And a10s if you didn't skip adds. After all, caster LB on 2 targets > melee LB on one so even caster LBing the boss+apanda on o3 would make sense if not for caster high personal dps. I can see SMN lbing there being the optimal solution in some compositions, however.
But in all cases mentioned caster LB is preferred over ranged LB. Ranged LB is harder to aim and *it deals less damage* (because they're support jobs, huh). I know BRD LB was reworked which brings me to the point...
Would it make ranged LB better if it just was damage reduction+hp/mana restore? It's still very niche but realistically ranged don't LB anyway and if it was half the tank lb mitigation and half the healer lb healing it could be useful (o4 springs to mind when sometimes after the healer death on some of the grand crosses the remaining healer has to deal with alma and heal lb usually doesn't help)?