I've dabbled in Enchanting. I'm around 29-33 or so in it.
Only problem with enchanting armour, is that you can only enchant it once (unless you have 100 Enchanting) and the enchants are insanely lower than robes.
Take the Arch Mage robes I just got, they have 3 enchants on them 15% reduction on all spells cast, +50 Magicka, 100% extra Magicka regeneration.
No Armour can rival that.
So far I'm casting Ironflesh and Flame Cloak on myself, charging in with a Burning Dagger and Fireball and blowing everything to hell
The change to dual heals when needed and it's all dandy.
With the robes and mask, plus a few items and Resto perks I have like 300% Magicka regen.
You need to find the items that reduce spell cost for certain schools of magic. This gives you infinite magic for 2 whole schools.
Max your enchanting to 100 (or drink an enchanting potion to raise your enchant skill up after getting it to like level 80), then find gear that has magic school reduction, and destroy it to learn the enchantment. You can reduce magic cost for a certain school up to 25%. An example would be, -25% cost to destruction spells, so the destruction spell only costs 75% of its normal base.
What this means is, with 4 pieces of armor, you can do -25% spell cost in destruction magic on each piece, making it a 100% reduction, meaning destruction spells cost 0 to cast. With the 100 enchanting perk, you can do 2 schools of magic free of magicka cost.
That's infinite magic for 2 entire spell schools (the two you use most). This is, in my opinion, the best way to go for an efficient mage, as you get the armor bonus of the light armor (dragonscale if you level smithing, but that's your choice) and 2 entire magic schools free of magicka cost.