Breton Mages

i've made 2 mages so far. one high elf pure mage and one dark elf Battle mage.
The High Elf does LOTS OF DAMAGE really fast but is kinda squishy so its best to do as stated above and use whats best vs your opponent.
Its mostly Destruction on her and some conjuration. along with enchanting. didn't really need to go into much else so i went into restoration a bit to get to the extra mana regen perk.
This setup requires you to use something like the equipment you get at the end of the mages guild to be the best it can.

My Dark Elf playstyle is more my own style of play. Spell in left hand (usually heal or one of the bolts cause i don't have high destruction yet) And either Bound Sword or Dawnbreaker (deadric quest reward) in the other. Maxing out Conjuration, Destruction, Heavy Armour, and One Handed. With plans to go into Enchanting and Smithing after i've maxed those 4.
I just summon an atronach/deadra switch to my fire bolt blast away while i run up to them and start swinging.
And the bound weapon is a decent weapon. Its basically a deadric Sword, and it lvs up your conjuration and one handed (or two handed or archer depending on what bound weapon spell you use.)