Flamethrower, as a capstone skill, really needs something to improve it. It's usage right now is limited to trash pulls where Air Anchor and Chainsaw have a cooldown greater than 10s and we don't have ricochet/gauss rounds to burn before hypercharge. And its damage increase over just using scattergun is questionable.

Have it accrue heat. Have it spend heat to increase its damage. Increase its base damage. It really is a terrible ability right now. Every expansion, I'm surprised it wasn't changed or removed.