It's too easy nowadays for any DD to cap CE and VE, resulting hate bouncing between them.
They should make an array of new PLD abilities that raise PLD's CE and VE cap temporarily. This way, they have to to juggle between these abilities to keep monster's attention on them. But still, they need all the requirement to keep thei CE and VE the highest in the group.
That is ultimately the problem. Damage generates so much hate that absolutely nothing in the game can possible overcome it. You can give PLD a JA that gives them 10,000 CE + 10,000 VE and put it on a 30s timer. They still won't be tanking for two reasons.
#1 Any DD can easily hit 20,000 TE within seconds.
#2 Once everyone is at the cap the target will be the last to do an action to the NM. DD's are wearing haste and receiving haste buffs, they will always
be hitting faster then the PLD and thus always be on the top of the list.
Now to those who still haven't really grasped how hate works. Absolute values for CE/VE do not matter, they could be 5,000, 10,000, 20,000 or 100,000,000 (assuming such was possible). What matters is relative
values. Nerfing the CE/VE produced from damage would not hurt anyone's tanking ability provided there was an equivalent nerf to cure hate as well. You would still generate the same relative hate as before, the only two differences being.
#1 Abilities that are primarily focused on hate generation become much more powerful as their hate generation is higher relative to damage. This is hinged upon SE altering them to provide a meaningful boost to CE.
#2 Hate reduction from damage stays the same or similar such that taking damage will actually reduce your hate by a meaningful amount.
Trying to give PLD a "higher hate cap" is gimmicky and won't actually fix the core hate mechanics. Why even bother bringing a PLD when a DD can hit the same hate and do 10x more damage. There needs to be a fundamental change in the nature of hate in FFXI, it needs to be centered on special purpose abilities rather then pure damage output. This issue isn't just FFXI, all MMO's run into the problem eventually where the DPS jobs are putting out so much damage that the system needs to be rigged in the tanks favor.
Two other changes I'd like to see for PLD would be having cover altered to force the NM to attack the PLD for it's duration and PLD being given a tool that lowers all entries (except the PLD) on the target monsters hate list.
Ohh and RDD, Shield Bash never was and never will be "hate tool", it has pitiful
enmity values. PLD's only real hates tools are Flash and Sentinel, though they also get Provoke from /WAR. Self curing was only acceptable in very bad XP parties, on NM fights the healer will be keeping the PLD topped off to prevent high damage moves from killing them. For PLD's it's pretty much cycling Flash / Voke while trying to hit as fast / hard as possible and mitigating CE bleed via damage intake.