I don't even see how we are playing the same game. I started yet another new toon, a scion 2H thrower, and just killed dom for the second time, norm/cruel, and he only dropped a single yellow item in both kills. I had to farm the docks from 50 to 54 for some reason, and I got no better than alchemy orbs and less than 20 yellow items and no orange items. I cannot believe that with all of my toons, the RNG hates me that much.
Dominus drop (normal difficulty) on my new dual-claw Duelist:
Merciless Dominus drop:
Decided to do some Vaal runs and also started swapping in my Item Rarity gem at kill and got this from my 4th Vaal run (63% total item rarity):
Quill Rain and another armour I'd never seen called Lightbane Raiment.