I agree that Defense is pretty important (+70 Defense with Sanction)
But I did sacrifice adding a lot of Vitality for the sake of STR and MND.
The main issues I was having with running PLD with a Defense/VIT and ENM build was that you didn't leave yourself much time to stop spamming attacks and skills to be able to dodge attacks.
The reason behind this build is that it generates a lot of Enmity through extra Damage + Combo Multipliers.
So much in fact, that you are able to dance around bosses and avoid heavy damage, without the worry of losing Hate.
The downside is the fact that you need to know the fights and be ready to move.