It seems much more advantageous to just wear armor and carry potions. If given the choice would you really rather have 0 armor and have to wait for mana to regen as opposed to being able to take hits?
As a mage I would have enough tools to NOT let them touch me :
1) Protective spells
Mage Armor line of spells - that gives you armor increase ( just like if you would wear some armor ) and there is perk that will highly increase magnitude of those spells ( if not wearing armor )
Circles of Protection - so meele enemies ( at least undead ) cannot come close
Alteration shield spell ( don't know how it works but can guess well enough )
2) Summoning spells
3) Status effect spells ( paralyze, fear, frenzy etc... )
4) Most offensive spells are ranged