The answer? Lots of Art assets
basically, have 4 art assets for every "high end" choice.
Also, have various robes and normal clothing that increase magical effectiveness.
For every Refolded Iron piece of equipment there is a Wizard's Exquisite Robe that reduces mana cost by 10% and increases spell attack by 10%.
Refolded Iron helmet(plate), Cuirass(plate), Greaves(plate-mail), Gloves (plate-mail) total of 40-60 or more defense
Wizard's Exquisite: Hood (silk cloth), Robe (silk cloth), Slippers (silk cloth), Gloves (silk cloth) total of 40% less mana cost, and 40% more spell attack/damage
There will probably also be enchanted rings, necklaces,, and Ear-rings that increase Magical Defense, Magical Attack, or Physical Defense, or any other stat.
Someone might want a suit of Refolded Armor, and 4 enchanted rings of Magical Defense.
Alternatively someone could want a Cloth outfit of 40% less mana cost and 40% more spell power, and buy 4 enchanted rings of physical defense.
Further still, someone could buy the Wizard's max outfit, and buy 5 rings of magical attack and 5 rings of magical defense. Making for the most uber and extreme Mage-Sovereign ever. ( I don't think it should be possible to go lower than 60% mana cost ... meaning you can't gain more than 40% mana discount) ... other than using Wisdom score of course.
Wisdom would probably use 1% per point, so 20 wisdom would have 10% lower mana cost, and 0 wisdom would have 10% increased mana cost. Intelligence would probably use 2% per point, so 20 intelligence would allow Spells to be bought for 20% less spell points, and 0 Intelligence would have Spells be bought at 20% more spell points.
Constitution could be 1 HP per point. So a 0 Con Sovereign could have 30 HP, a 10 Con Sov could have 40 HP, and a 20 Con Sov could have 50 HP. A Hardy 20 Con Sov could have 60 HP, while a Hardy 10 Con Sov would have 50 HP.
I don't mind Strength and Dexterity to give % bonuses to your equipment score. I think I rather like it. Each point giving 10% with 10 strength or Dex being 100% of the Equipment's stats. I would, however, advise for a weaponless Sovereign to have a base "fist" attack of 2, and a base "reflex" defense of 2. Having the Hardy trait would double these base values, and gaining the Monk trait through quest (taught the ways of the monk) would quadruple these values, as well as add +5 to Attack, Defense, and Wisdom.
Hardy and Monk do not stack. Monk also increases HP by 10. In addition, if you gain the Monk trait, your Wisdom score (if higher than your Strength or Dexterity score) can replace your Strength or Dexterity in terms of affecting Attack and Defense with either no Weapons + Armor or only equipped with Staff + robes/cloth.
So if you have 40 HP, 5 strength, 20 wisdom, and 5 dexterity. And you have no weapons and no armor ... you would normally have 1 attack and 1 defense. However, once you gain the Monk trait through questing, you would have 50 HP, 10 strength, 25 wisdom, 10 dexterity, and no weapons or armor. You would also have 20 attack and 20 defense.