Warriors and Paladins have the same effective health, roughly. Keep in mind that Shield Oath exists alongside Defiance.

Parry is actually more important on a Warrior as that is literally the only stat-based mitigation a Warrior has. Stacking STR is something to consider, but not OVER Parry. Even with pentamelded Gryphonskin you want to cap the Parry on it as one of your highest priorities (behind VIT).

Of course, as this thread shows, Parry isn't that great because of how little bang for your buck you get per increase (or just in general). This is true of all the secondary stats except Accuracy and (sort of) Determination. You shouldn't ignore Parry all together, though, especially as a WAR.