The payload quality seems to be ignored, launching a stack of legendary destroyer capsules or legendary cluster nades does create normal quality ones in the target area. Is it an oversight or intentional balancing decision?

With mods like Rampant, normal quality becomes quite useless as the game progresses.

To be honest I'm not sure if I can do anything about it.
My mod checks the ammo definition directly and spawns projectiles based on their content (which does not change with quality I think).

I'll see what I can do without sacrificing compatibility with modded ammo or breaking the balancing.