If you could use the heritage armor on all races, yeah I'd do it on every single allied race. But since you can't I'll just limit myself to another one (already done Void Elf). I've leveled every class to 110 before the changes and it was definitely a lot faster.
(And yes it FEELS faster at some points, but over the whole 20-110 it isn't. How it feels is irrelevant if my actual time invested is a lot more than before)
I do love that if I quest, I can now actually finish a zone without outleveling it and I can skip whole expansions. Great change, but as someone that mainly leveled with dungeons, it just got tedious. The dungeons didn't get harder, they're just longer. As a tank I can still pull a crazy amount and take barely any damage, the only difference is that the mobs take 5x as long to die making the whole leveling process longer.
Now if they increased the damage of the mobs so you actually require some knowledge of your class to keep pulling the way we did before, I'd be all in for that. Or just increase the dmg to match the hp and increase the exp gain to balance out the new "difficulty" and I'd be happy. But simply increasing hp didn't make anything more difficult though.