This is my attempt at making Balefire worth using.

Balefire's explosion radius scales with Ability Range and [Fulmination]. I like to take advantage of both options simultaneously for maximum AoE.

[Balefire Surge] and [Augur Reach] are not strictly neccessary. [Blazing Pillage] is a good alternative. You could also use Shield Capacity or Recharge mods such as [Augur Accord], [Boreal's Hatred] or [Fast Deflection] instead. [Streamline] works, too.

[Umbral Intensify] can be replaced with [Augur Secrets]. This saves 1 Forma and still allows you to remove 100% of enemy shields with Pillage as long as Roar is active.

[Enemy Radar] is essentially a placeholder. Feel free to use any Aura you like. [Pistol Amp] could work nicely if you have some Forma to spare.