Our problem with that gun is that it's used too much, right? It's used too much because it works better than any other piercing/explosive combo at the moment.
Keeping that in mind, let's compare: The light flak deals medium damage on a high accuracy and quite medium range. The mortar currently can hit on the same range with some mediocre-high accuracy, but deals much more damage.
One could say "just decrease the damage and it's fine". Yeah, you might think so, but decreasing damage will still leave us with a gun that has a range capacity from pretty close to quite medium and mediocre-high accuracy. That means we have a flak we need to arc to hit. This would provide the only difference, making the flak the way to go since it would be easier to hit.
Instead we should think about what to use the mortar for, what to specialize it in. And this would be close quarter combat, I think. Take the flak if you want to stay a bit more on range, like a mobula with it's weak hull but more guns aiming at one target. Take the mortar if you want to get close and cuddly, like on a pyramidion where you can use it's strenght - ramming.
Thinking about that we need to change something, so the mortar would be used mainly in CQC. I think about decreasing range, since you can't change it to spread it's shots more. But since we don't want the mortar to only hit when already cuddling with the enemy, I say decrease it a bit and decrease the damage as well a tiny bit, to compensate for that.
Those are my thoughts on it.
@Queso:
First I notice is that this takes many changes on different objects.
But I'm with you about bumping up the heavy flak's clip size by one. I don't think the clip sizes (on the light flak not at all) should be increased over 9000, because that would lead to piercing/explosive combo being OP again, but a little bit on the heavy might solve that problem too.
More hull health is something I don't want to see. It's already quite good the way it is - never touch a running system!
