The ins and outs of armor/HP Buffing

Additional Armor:
Against All: Armor of Earth, Armor of Mist, Kinetic Armor, Obsidian Flesh, Shield of regeneration, Fertile Season, “Watch Yourself!” (shout),Disciplined Stance, Defensive Stance, Dolyak Signet, Defy Pain (elite), Ward Against Harm
Against Physical: Armor of Frost,Physical Resistance
Against Elemental: Ward Against Elements, Dryder’s Defenses , Elemental Resistance

The only non-removable armor is that from “Watch Yourself!”, Dolyak Signet, Defy Pain, and Ward Against Harm.

Increased Max Health:
Skill: Defy Pain, Endure Pain
Enchantment: Vital blessing, Demonic Flesh
Spirit: Symbiosis, Fertile Season

Correct me if I'm wrong, but "Physical Resistance" should belong in the second catagory rather than the first since it gives you an armor penalty against elemental damage when it is in effect. That, and "Armor of Frost" works against elemental damage as well, I believe, but it gets stripped if you take fire damage.

You're right on the first count but wrong on the second. Armor of Frost is just another reason the Water line sucks. (Or, if you prefer, is undervalued by elementalists.)

Armor of Frost is canceled when you use Fire Magic (and has a -24AL vs fire malus.)

In the health boost, you have not listed Symbiosis.

There might be more (like Convert Hexes armor boost) but not that I can think of right now.

You missed Symbiosis and Fertile Season for the HP buffs, and "Shields Up!" in the armor section.

Edit: And Ward against Harm.

Water Hexes + FoC = Fun