Or amplified

That’d be too strong if I’m being honest

Eh. For me the biggest issue that can arise is risk runner being enemy dependent and unfortunately arc doesn't have many inherently good was to proc the effects. Alternatives could be it activates when debuffing an enemy with arc debuffs, damaging/killing a certain number of enemies to proc (like one for all) or proc on the reload (like kill clip). I think the the gun is great in pve but gets held back by the unreliable uptime on the exotic perk. This includes using self damage from arc grenades to proc it. Sunshot and graviton lance are consistent in their effects even though all of them are decent (I personally think sunshot is kind of garbage, but I know other don't). A final equalizer would be letting the explosion from graviton inflict volatile, and risk runner jolt its affected targets. This would let all 3 build into their subclasses without jumping through hoops.