Green, Blue or Purple Armour.
Clay Fragments (Then higher ones too as you level up as these are permanent buffs)
Moulds for above armour (Stay with your armour, can be bought again to "gamble" for better buffs)
Runes for above armour (Stay with your armour, can be upgraded)
Talents (Permanent buffs that can be bought with books & Truth Crystals, or, are level/achievement dependant, in most cases. These can be changed/swapped/reset for Travel Stones if you want as you usually get choices of buff for each Talent that you may want to change as you progress)
That should keep you busy for a while