1. PLD can tank in Sword Oath. It may be harder to hold hate but y'know, your co-tank and NINs exist. WAR? Unchained+Berserk. DRK? DRK. I honestly don't know what they do other than pure damage after the first two PS.
2. OT exists.
3. What are you suggesting? PLD ShO does equal to DRK no Grit? And then DRK still eats -20% with Grit on?
4. New patch. For all we know it's probably gonna be alot harder to even hold hate outside of tank stance with the DPS nerf. PLD's Savage Blade(which is also in RA combo) enmity got buffed for a little extra(though needed) sprinkling. ShO Damage penalty got reduced to -15% vs Grit(-20%). GB and RA potency buffs.