Will Update this as I get things, Feel free to contribute Grinding Spots or Other Information.

Bags
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8 Slot – x10 Stretched Rawhide Leather Square or x20 Rawhide Leather Section
10 Slot – x10 Cured Thin Leather Square or x20 Thin Leather Section
and Minor Rune of Holding (4 Silver 96 Copper)
12 Slot – x10 Cured Leather Square or x20 Coarse Leather Section
And Rune of Holding (14 Silver 80 Copper)
15 Slot – x10 Cured Rugged Leather Square or x20 Rugged Leather Section and Major Rune of Holding (50 Silver)
18 Slot – x10 Cured Thick Leather Square or x20 Thick Leather Section and Greater Rune of Holding (2 Gold)
20 Slot – x10 Cured Hardened Leather Square or x20 Hardened Leather Section AND Superior Rune of Holding (10 Gold)

End Game Leather Sets – LvL 80 Orange Gear. Best I have Found.
Berserker's – +Power, +Crit Damage, +Precision
Rampager's – +Precision, +Condition Damage, +Power
Knights – +Toughness, +Power, +Precision
Explorers – +Magic Find, +Power, Precision
Carrion – +Condition Damage, +Power, +Vitality
Cleric's – + Healing Power, +Power, +Toughness
Valkyrie – +Power, +Critical Damage, +Vitality

Each one comes with a Gem Slot too

The Above Crafted Sets seem to be as good a quality as the Dungeon Sets or Karma Sets; Stats Wise. And Blows the Racial Armor Sets out of the Water.

Just pick the set you want, you can mix and match, and I can give you a list of mats you have to get. Then I will craft it for you. Just Send me a Mail in Game.

Found out that you can get the first type of leather off the centaurs in the Human's starting event; like at the very beginning when have you tell the villagers to get to the inn. They respawn super fast and you can get leather, jute, claws, blood, totems, and bone.

Updated with Final Bags and End Game Sets.