This starts to paint a picture that I've never seen, taken as information from multiple units.

It would appear that there may be some rhyme or reason to this distribution of firearm types. It looks like there may be a reason that the type of arms was mixed, perhaps different troopers were used in different ways tactically, and that the weapon that they carried were for a certan purpose based on their assignment. Else, why not just consolidate and re-issue weapons all of one type to one unit? That method would certainly have advantages unless there was some other purpose for the mixed distribution. And, the final statement seems to imply that this unit should have a certain number of certain type arms.