What job is the highest priority to fix?

[Rhais]

Talking with my friend the other night, we were discussing how uncreative a lot of the ShB changes were; in particular Delirium being a IR clone comes to mind. Even a lot of the jobs as a whole feel too simplified. Bard, Astro—though the healers as a whole suffer in this regard. And it all comes down to this. They desperately need some fresh ideas, and frankly, more people to help execute them. Shadowbringer has really highlighted this because I cannot recall a period where so many jobs have been hit or miss.

What you are describing is intentional, I don't think it's so much a lack of fresh ideas as much as deliberately simplifying all jobs and making all jobs within the roles function in a similar manner.
I suppose they are going for accessibility and job balance, but it certainly is making combat less engaging in my opinion.