I agree.
I've only been playing 3 months & I already have several hundred of all but 1 of the items in this challenge.
I think one of the biggest issues is when a character gear tier is created they don't put any (much) thought into what goes on the character.
There are items in the game that only get used on a very small % of the characters but in turn you get items for those slots all the time & rarely for the items that get used many times over.
I'm also not sure why some of the gear STAT choices are made.
I guess I come from games where if you are a STR character you use quite a few STR items & quite a few All/Multi Stat items, but you wouldn't have an piece of gear that is pure AGI(Dex) or pure TAC(Int/Wis).
Yet I see Carbantis-3 (25 STR) by themselves all the time on Attackers, Support, Healers.
Why not use a Carbanti-1 (25 ALL) more often? We have a bunch of parts for those.
Or Change the Stats for the Carbanti-3 to be 50 STR so that its clearly better at something as a Purple Item then the earlier tier Carbanti-1 that has better stats (25 STR/AGI/TAC)
I look at the items on some characters & can only think, "well this was chosen purely to make it hard to get v/s character class driven". (2 Stun Guns on the same level?? Really?? Really???)