Right now all weapons fire based on a fixed cooldown delay. What this means visually it that if several ships start firing simultaneously, for example if an enemy fleet jumps into the gravwell, that group of ships will *always* fire simultaneously for the duration of the engagement.
It's hard to imagine crews being able to coordinate their fire that perfectly, down to the fraction of a second. It looks especially bad when rapid fire weapons (such as those on the flak frigate) are involved. Two dozen or more machine guns, all firing every bullet in perfect unison? It breaks immersion.
There are also gameplay consequences for this massed fire. All too often, many ships will select the same target, so much of the salvo can be wasted firepower.
I think adding a random component to weapon cooldowns on a shot by shot basis would help both the visuals and gameplay by breaking up these massed salvos in large engagements. Of course, the random factor should be ship-specific (and moddable) so that massed salvos can be maintained if desired.