Weighted drops are really great and usefull feature, however they should not be applied to overland gear. In current state WD can be very easy exploited to target farm certain rare and valuable weapons \ equipment gear, drastically improving chances of getting rare combinations from 1:120 (for all available weapons and their traits + 2 gear slots in drop lists) up to 1:8 for killing World/Public Dungeon Bosses. You just need to fill your collection for this zone with every gear in loot table for bosses EXCEPT targeted weapons. By doing so, you can basically just go and print something like Inferno Spinners staffs (or Bright-Throats, or Briarheart daggers, or any other popular gear), flooding and completely destroying market. I already saw today some examples of it, with people magically taking out of their pockets 5+ inferno staffs for rare sets, and, after they got sold, taking even more of them out of magic pocket.
The whole point of WD system was to help people with grinding for sets from arenas\dungeons\trials, because you just don't have other options to get it, only farming and praying for rng. WIth world sets situation is a little different, you actually can get them without grinding by just buying them. And it is a way for some players to get some gold not only by doing regular writs+mats farming. And yes, i get it, no all account can benefit from it, because rare items in collections were already collected, but it doesn't mean this wont become an issue pretty fast.
So this system should be at least some how limited or totally disabled for world drops, or very soon it will be absolutely no reason for people in farming world sets for getting gold.