I think the fact of having a pet that never progressed or changed made DRG from XI in my eyes a bit of a gimmick. What they've done with DRG in XIV is way more enjoyable as it attaches the storyline.

Class uniqueness doesn't need to lend itself to a pet. I'd prefer a unique play style. For example, let's say DRG is the best dps in the game, I rather Jump-style abilities play a role in shedding hate. That way when I play DRG I need to be constantly aware of my hate to throttle my damage for the sake of a HNM, Moogle fight, etc.. That could be but one way class uniqueness is implemented.