Too many players, me included, have recieved an absurd number of red duplicates, usally a single item. In my case I have 9 red charms. Also, the trait/stat rerolling system is a joke; the fact that I have rerolled the same trait 4-5 times in a row on an item is infuriating.
Vermintide 1 had systems in place to balance the RNG; no red dupliactes, being able to re roll either value or property seperatley on items, and not being able to roll the same trait again.
I would suggest implementing these features again, in addition to a red crafting system, as a means for players to actually use all these red dupes.