>>5434373Theoretically all turrets are modular. Just think about how many Russ variants there are. There's also variants of the Malcador and Macharius too where they just switch out the gun.
I do agree that the speediest thing to do is just resort to the basic battlecannon get them off the production line, with plans to implement more prototype standardization, is likely wise. Just like we did by shifting away from bolters to volkites, we did dedicated effort to make that happen and it did.
I believe developing at least the twin-linked Lancer Laser Destroyers as a standard armament relatively soonish is doable. Laser Tech is the Imperium's specialty. If the shattered Imperium facing the crisis of the Great Rift could start mass producing them from Cawl just saying "LOOK AT MY NEW TANK!" and everyone starts churning them out by order of Guilliman, certainly we of the 30k Mechanicum and our own realm could at least match that right?
Do think the Twin Magma Melta with Beamer extension is better and should be our final pursued weapon. As a Blast weapon it gives it great soft power against infantry squads, while that -4 AP will make it much more likely to wound enemy armor than the Lance's -3.