Here are my ideas for builds so far.
Full Brawler
Gatling top left
Gatling top right
Flak lower left
Flak lower right
Banshee centre
The idea here is pretty obvious. There's an enormous angle in which you can land gatflak on the enemy ship, with the banshee adding extra support. I'm assuming that the hull is hidden below deck, which is why the flaks are down below. The gat needs to be firing more often than the flak, so this setup allows the lower gunner to do some hull repairs. It also allows for more trifecta arc.
Alternate Brawler
Lower left flak
Lower right flak
Upper left banshee
Upper right banshee
Centre gatling
The idea here is the same in principle. It's just shifting the use of the gat to the engi who'll be doing less repairs (up top). This allows them to spend more time on the gatling, and they won't have any gun switching to do. Banshees are still there for the trifecta.
Brawler/Utility
Upper left gatling
Lower left flak
Upper right mine launcher
Lower right flare gun
Centre banshee
This one makes only one of the sides be used for fighting with the other meant for utility. Not much else to say.
Sniper
Right side mercs
Left side gatflak
Front Artemis
Simple enough. Mercs and an Artemis for long-range fighting, gatflak when they get close.
I'm not sure if the banshee is the best trifecta gun. With this ship, you'd better be killing as quickly as possible. Maybe an extra flak or gat would do the trick?