Now that's actually really nice, I like the new morale rules a lot.
Firstly it takes away disagreements on wether a unit did take a morale test or not. And if a player has started his own turn, it's too late to claim any morale tests should be taken by the other player.
Just like in monopoly if you fail to cash in your rent before you roll the dices, no rent can be charged. Opportunity missed!
Secondly armour does not impact wether you loose a model or not, a fleeing terminator runs away just as much as a grot once they have failed their Ld test. In previous Combat resolution morale tests, good armour was a thing.
"Thirdly?"(might even split into two reasons) small elite units does not run away just because they lost a percentage of their unit, it also saves some calculations, and removes morale optimized unit sizes.
"Fourthly?"Single models left as stragglers not fleeing, by default becomes immune to morale.
Sure elite units may loose extra models, but that just make the Ld value just as important as toughness or armour save to stay on the board.