The reason why WAR has lifesteal at all is because this game was only released with two tanks. DPS jobs have a lot less identity issues because there was five at launch. Imagine if BLM was the only caster at launch, and you gave them the ability to use summon magic. When SMN comes along, how do you make it feel unique? Imagine if you put Trick Attack, Mug, and Mudras on MNK before NIN was released? How could you be expected to differentiate it after the fact? The reason why Tanks and Healers run into so many problems is because the two-job design of these roles actively stifles new job development. We have to make room for new jobs to build their own niches.

It's not an issue of job power. It's an issue of aesthetics. Take Thrill of Battle, for example. You gain temporary HP to shrug off damage. It's a form of self-healing, but it fits with WAR's overall aesthetic. Casting curative magic and draining life are features that make sense on magically oriented tanks. Parry moves make sense on tanks that use a weapon with finesse. If you're playing a Berserker type job, it makes more sense to just fight through the pain. IB and Steel Cyclone could very easily have been built on similar principles without compromising other tanks' identity. Let IB and Steel Cyclone give temporary HP based on the damage you deal. Leave the vampiric tricks to tanks who have the magic and the lore to support it.