yea, "Change gun 'A' display name to 'B'" and "Change gun 'A' display name to match string value of variable 'B'" would be good to have, a way to have custom bullet models/colors would be good too.
From Eric: Guns can't be renamed because they don't keep their names, but only IDs that later are converted into names. Also it would break compatibility with PB2.5/3 as guns there are done differently and there is actually a class object that defines all these special properties instead.