Like other people have been saying, when you start dealing with higher level monsters, the small amount of damage reduction from increasing defense is impotent in the face of boosting offensive power. This wouldn't be an issue if we could put up as many buffs as we want, like how Whms throw up Protect just because hey, it doesn't hurt anything, but Cors only get two slots for their buffs. It's not resource efficient.

Here's the point where I make a suggestion. If you really don't want to give us Phalanx that badly. Change Gallant's Roll to reduce the damage from AoE abilities and spells from mobs. Something like Scherzo or Earthern Armor that only works on AoE. That's something you wanted to focus on in Voidwatch and Legion right? If it's a decent boost I'd sure use that in a tank party.