The OP has beautifully worded the shortcomings in this MSQ. And I find it funny that I as well, talked to every npc before continuing the next quest in previous expansions.
Because they all had their own character specific thing to say.
And I started following this trend in Dawntrail as well, but in the 3rd zone I began to stop doing that because none of them really said anything interesting/captivating most of the time.
I felt really detached from the characters in this MSQ and I tried really hard to like them. The only moment where the story and its characters got their hooks on me, was during the entire Mamook section.