Remember that the best defense is a good offense! And theres nothing more offensive then barraging your enemy and taking them down with shock and awe. Improve your fleets offensive firepower and have the enemies sweating by adding the Artillery ship to your roster.
The artillery ship provides great fire support during long range engagements. It is also very good at weakening tight formations of enemy ships. The weakness of the artillery ship is in close engagements (so blow them away from a distance).