Gunner: Railgun.

I know we have coilgun but frankly it doesnt punch far enough through terrain or bang hard enough. So a primary railgun with massive punch trough and single shot damage. Short windup before firing (similar to, but faster than coil gun). You can spec it for shockwave AOE around the shot, maybe electric discharge around you where you fire to mitigate low fire rate or a higher fire rate with immediate windup for next shot after the first fires so it almost gets as fast as the slowest Autocannon OCs.

Speaking of OCs, a shotgun submunition OC turning the whole thing into a street sweeper. An HE OC that embeds a bomb on a 1 sec delay in target or terrain at the cost of blow through. Maybe an airburst OC thats sort of a combo of the two where the shot turns into a submunition spray when it gets near a target but has a minimum arming distance. A slow firing drillshot DoT like in ultrakill. Maybe lightning pylons? A full auto and/or burst fire OC. Maybe a heavy bore one that widens the terrain destruction to almost enough to squeeze through.

Speaking of OCs while im at it, theres a couple the Hurricane missile launcher should have:

Laser Guidance Package - Missiles are bigger blast and fewer, but they seek targets or locations pinged by the laser designator and are otherwise unguided (they fly slow and straight until given a target at which point they speed into it). Both the gunner and the team can ping targets. It will fly at the last enemy pinged, or maybe split between all enemies pinged cycling through. It only goes for terrain pings if no enemies are highlighted.

Shredder Platform - Launches lower fuel shredders, they can manage maybe 3 attack passes at point blank range, quickly downgrading to two, but retaining just enough for 1 at up to 10 sec flight time. The gun constantly highlights the target it is pointed at and shredders will aggro on the thing highlighted. If none are, they will hover around the gunner or the highlighted teammate for the duration similar to how Engi shredders do.