there is two schools
- the max endurance, with the fortitude augment, relying a lot on self regen being a % of your life.
- the damage mitigation: i choose personnaly full absorb, to make use of our high shield chance.
Don't go defense or offensive stat (willpower, accuracy...) it's not needed to hold aggro.
Max Endurance: You will get pummeled on most fights and your healers will hate you. There are exceptions like the Stormcaller tank or Soa because their attacks are mostly Elemental and can't be mitigated by def-stats anyways.
Max Absorb: Bad aswell without a reasonable amount of def.
Personally I'd go for Ktru's and KeyboardNinja's weighting: 30% Def, 45/65%(with Dark Ward) shield, 60% Absorb