Fashion report - great concept, lousy implentation.
#1 Your players aren't made of gil
Stagnation is bad, but speculation is worse. Watching your one size fits all item get jacked kills it for poor players. If that item is out of their reach because it's not easily obtainable then it kills participation and incentive to experiment.
#2 Weekly limit.
See above, market price spikes are bad enough, (removing dyes from scoring is a band aid solution) but 4 tries a week with ambiguous hints on top of the one size fits all solution means good luck finding it without cheating.
#3 It's Fashion report, not fashion 'Reddit'
See both above, the scoring is so tight on it's demands for that 'perfect' item, to the point where one shiva item works but another doesn't for a 100? The heck?
#4 Class locked challenges / items.
Now throw on top a one size fits all where you need the right class to get the score? Again, you're needlessly locking your minigame behind some stupid arbitrary restrictions. And you wouldn't have to if...