If you have an arcane slot for it then you can put primary merciless since if you aim at a strong enemy like a Nox or heavy gunner,

it will chain to nearby enemys, boosting damage while you damage the heavy gunner or whatever tanky enemy you are shooting, if you have primary merciless on.

if you want you can rearrange the 60/60 elementals to whatever combo you but i recommend this setup or something with corrosive,
and since it can basically proc two times with one round, if given even stat chance, you can proc viral a few times while build up heat,
increasing damage to that target which works well with [Galvanized Shot].

And multishot to basically double, triple, or quadruple Most of it.

you can also replace lethal torrent with some amazing riven, like multishot and/or increased damage to say some of them.

ALthough it would burn through ammo pretty quick so if you maybe add a forma or two you could on an ammo mutation just in case.