Staffmods already make uniques useless over runewords. Hell there are white vendor items that are better than uniques and sets because of staff mods. I covered this extensively in the last PTR:
The set “improvements” were all in modifying set bonuses but no modifications were made to individual pieces.
There needs to be a complete overhaul of set items to make partial sets or individual pieces more useful. Right now, low level individual set pieces are basically equivalent to magic items with 2 fixed attribute rolls. That makes them far inferior to rares and uniques and outright useless against low level runewords.
On a fresh start, how often do you actually use low level set pieces that drop? That’s the barometer for how useless the set pieces are compared to equivalent drops at specified ilvl zone.
Here were some suggestions from last PTR:
There is no way to get back to 4 frames now, there needs to be some means of improving damage by at least 25% just to get the set back to 2.4 damage output at 5 frames.
Improvements to sets also require improvements to the individual pieces of the sets.
BK set is completely useless unless the damage on the weapons is increased. Double Unbending Will far exceeds the the damage of BK pieces and is far easier to find.