I meant between the kinetic broadside and the plasma broadside - the reload, damage and range seem in the same gameplay reach. Scatterguns are nearly melee weapons and reload very quickly, so, dps and clear gameplay. But the other two i'm still experimenting.
The Plasma Broadside at T4 has 16s cd and 12k dmg, the Scattergun Broadside 5s cd and 7k dmg, with the Module Amper Briefing (+30% module damage when power to weapons) and enough energy for it this turns into 15.6k and 9.1k, so the Plasma Broadside has the higher "burst" and reach with 2.4km. The Scattergun Broadside has a 900m range and wins at raw dps with 1.4k versus 750 for the Plasma or boosted 1.82k vs 975.
And by howitzers i meant mortar turrets.
One shot, 4k damage, rather long reload ~4s, shoots four projectiles on a slightly arcing trajectory that spread out over distance but have a small aoe and no damage fall off over distance.