I would level Alteration a little too. Being a mage it helps to have the Ironflesh type spells to make you less squishy incase somebody gets through your summon and starts wailing on you.
Sneak and Archery are no problem either. Both are useful for those sneak attacks from far away, and I don't see it overleveling you because they're both semi-combat at least. Over leveling is when you grind Enchanting or Smithing or Pickpocket or something, and then end up having level 20 Destruction to fight level 20 monsters.