I did some very quick testing as PLD and it didn't take too long to figure out that some of the best builds are most likely going to be composed of having a lot of VIT, HP, magic evasion/resistance(sitautional) and some ENM where you can get it.

MND- is terrible for curing potency and gives terrible MP to boot. If you really want to be able to heal yourself as PLD somewhat effectively you'd be better off stacking healing magic potency. MND is also not the greatest thing when it comes to auto attack damage. I used a cobalt winglet with +32 MND on it and it was less than half of the amount of dmg i did on the same mob same exact lvl with an Ifrit's Blade. Even at MND cap it still wasn't really making enough of a noticeable difference on the flat blade combo which is a waste of TP and a combo in any boss fight. So I've concluded that for the most part MND isn't really going to do much for you. However, I wouldn't completely overlook it just yet because i have further testing to do but as of now i just don't see it doing that much.

STR- Be better off stacking AP and you won't get enough blocks in on any endgame to make the damage mitigation worth your while. You'd probably end up losing a lot of tanking potential trying to stack this.

DEX- You have to stack A LOT to make a semi noticeable difference, and you're either going to have spend and ungodly amount in melding or you're going to have to give up a lot more useful stats like VIT or even MND for that matter. For now, DEX just doesn't seem that good of a thing to stack. Especially since the block you obtain from DEX just doesn't seem to cut it in end game content. You'd honestly be better of stacking raw block rate.

Defense- We should all know that defense is messed up for anything worth your while.

HP- You get more of it you can take a bigger hit, congrats. It's also an amazing modifier for Spirit's Within which is your primary hate grabbing WS. I actually know a buddy who stacks nothing but HP and he tanks very well and he doesn't even stack ENM like some recommend you should.

VIT- Unlike defense, this actually makes a noticeable difference in damage mitigation and it also modifies your WS's. I would recommend at least getting it to the soft cap which is 350.

Magic Evasion/Elemental Magic Resistance- Recently, I've noticed that if you stack enough of this or at least switch up some of your gear for things that have this it will make a big difference on the damage you take from magic(even in endgame content).

Enmity- Many tanks love to stack this for days. However, ENM is not something that you desperately need on PLD. In actuality i find the ENM is more useful for WAR's than for PLD. I've seen PLD's tanking amazingly with little or no ENM. It is good to have some of it but it's not your greatest focus nor your greatest asset. I found that VIT and HP help more than ENM when it comes to getting hate and keeping it. So get it some if you want just don't go too crazy for it.