I think you are limited to 10 components at the moment. The dreadnought has a bridge, engine, launcher and three shield emitters so not enough components left for the seven plasmas on that ship. Hey why not make them actual plasma turrets? Use the same turret type as the barracuda which has no moving parts. Could look quite cool in game play.
That could work. you'd have to give them enough hit points to take a few HARMs or one light torpedo each, but you could still create a nice destroyed mesh for them.