The three sets that can be collected from veteran dungeons (Worm Cult / Hircine's Veneer / Ebon Armor) all share one common bonus which is
- Adds 4% Healing Taken
For Ebon Armor that bonus is probably within the theme of tanking, but for the other two it doesn't make any sense at all.
Now these sets are very hard to get; the drop rate is extremely low and it can get months to farm them. That's not a bad thing necessarily as their 5-piece bonuses are pretty sweet. But it would make them far more desirable and worth farming
if instead of healing taken, they had another useful bonus relevant to the set.
Needless to say for the Hircine's set that would be either stam regen, max stam or wpn damage. For the Worm cult set exactly the same but magicka instead of stamina. For me ideally the set bonuses would look like this:
- 2-piece: Adds [Spell /Weapon] Damage
- 3-piece: Adds Max [Stamina / Magicka]
- 4-piece: Adds [Stamina / Magicka] Recovery
- 5-piece: Reduces cost of [Magicka / Stamina] abilities for group
Adding screenshots from 1.5 for posterity (obviously a bit outdated, but the values are now approximately multiplied by 10)



Also please,
please remove that ugly glow that surrounds you when you wear 5 pieces (blue / red /green, depending on set). Apart from completely ruining your appearance it also reveals to opponents/teammates what sets you are wearing which can be controversial.
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