[Hystrix Prime] is a good weapon but it suffers from slow reload speed and small magazine.
To fix this, Primed Quickdraw is mandatory to help sustaining the DPS.
[Ice Storm] also adds 6 bullets in your magazine so it's worth slotting it instead of [Frostbite]. As Viral stacks are capped to 10, you won't even notice the status decrease.
Cascadia Flare is obviously the best choice for a Viral/Heat build.
The downside of this weapon is that it requires Arcane Velocity on your Warframe to be really effective.
Link to the Corrosive/Electricity https://overframe.gg/build/358180/ (Config B)