I'm wondering this strictly for the purposes of hunts where the number of people present is only going to allow them to live for 20-60 seconds or so and I want to generate enough enmity to get full credit before it dies.

WAR seems like it would have the highest generation over a longer period of time between Berserk, Unchained, and Onslaught, but it also has a wind-up time due to the Storm's Path buff accounting for quite a bit of damage.

PLD and DRK seem similar in that they lack wind-up and can go straight into spamming their enmity combo with Fight or Flight or Blood Weapon + Dark Arts which probably makes them better for short-lived hunts, but I'm unsure of how they'd stack up over a longer period of time.