Whenever I destroy a concussion mech, the missiles it released bounce around with the explosion before coming to rest, never to move again. It would be logical for the powerups to move again whenever another explosion goes off nearby. Perhaps keys and such could continue to ignore collisions, but at least for floating missiles, it would make sense to be able to move them, either with the pyro, with explosions, or by other robots. I remember using the blackshark missile in Descent 3 to move weapons and ammo around a room, and I always liked this feature. In Descent 3 I dont recall being able to move powerups around causing premature missile detonation or similar problems, so it should be possible to implement this feature without breaking any functionality. Maybe this feature occurs to me because I am using the full 3d models for all powerups.