How will loot work with the Legion content?

Genuine question.

I’ve played the game for a while and have reached 1400, the gameplay is fun but the gearing is frustrating. Out of 6 main stats, 3 of them is completely useless and are never used (that I have seen), and there are like 10 viable engravings out of like 40 while the rest are completely useless, meaning that 99,9% of the time you will get items that are completely worthless. Of all the time I have spent in the game in T3, I have never once received an optimal accessory with my main stat and the engravings that I want, stones are even worse since if you are unlucky cutting them they can be completely useless and on average it will take quite a few stone before you get a good one.

So the “correct” way to get the good stuff is to buy it from the auction house, but that is limited to how many Pheons you have since it cannot be farmed or gained normally through gameplay. Does anyone have any insight in how it will work with the Legion content? Will there be a way to actually work towards getting the optimal gear yourself or will auction house still be the primary way?