Altogether, you will need a Light Armor skill of 70, a Smithing skill of 100, and 13 skill points, on top of the skill/skillpoints needed in Alteration if you want to use the protection spells to further buff your armor rating. Using Light Armor, you can reach armor ratings suitable for a fighter-class character despite still being a 'mage.' The downside is the immense skill and skillpoints needed for this method. If you were able to use the previously mentioned spells and still have Magicka left over for other spells you need to attack, then the armor ratings would go as follows: This already surpasses the Mage Armor trick by far in terms of armor rating, but you can still improve. Note that this is without the use of Fortify Smithing potions or any other effects. Now apply the 150% increase from the perks, and you have an armor rating of 405. Or, even better, if all four pieces of armor had been improved to Legendary on a workbench, they normally get +20 armor per piece for the improvement, which brings base armor rating up to 162. Maxing these perks out requires 7 skillpoints and a Light Armor skill of 70, but it will bring this base rating up 150% to 205. This can be further improved through the Agile Defender, Custom Fit, and Matching Set perks in the Light Armor tree.

If we assume that Dragonscale armor is being used, there is a base armor rating of 82 (not including the shield of course, because we are a mage). On the other hand, Light Armor will give you a permanent armor rating, and with the Unhindered perk, it too does not weigh anything. This adds up to a lot of Magicka being used during a fight that could be used on damaging the opponent. The downside is that it still costs Magicka to use the protection spell of choice, which takes away from how much you have left to use to attack.ДЄlso, since these spells all last for one minute, you will have to remember to do this every 60 seconds, every time you want to have armor. The Oakflesh, Stoneflesh, Ironflesh, and Ebonyflesh spells affect armor rating directly, so here is what your armor rating would be depending on which spell you're using and the level of the perk.ДЄs you can see, it's possible to obtain an armor rating of 300 with no armor. This perk multiplies by 2x with one skillpoint, 2.5x with two points, and 3x with three points. The catch to this is the Mage Armor perk, which multiplies the effect of the protective Oakflesh, Stoneflesh, Ironflesh, Ebonyflesh, and Dragonhide spells if no armor is equipped whatsoever. Additionally, Light Armor/no armor lets you move faster and be more quiet than Heavy does, and Heavy doesn't really fit the mage's role anyway. I think Heavy would be out of the question, because personally I don't find the perks in the Heavy Armor skilltree to be as useful. And I'm assuming you're going for a mage-type character.

Ok, so there's 3 options here: Heavy Armor, Light Armor, and no armor/robes.

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