I was doing well with my frost mage until I decided to respec my druid to boomkin.
I was doing about 900 dps on my mage who is considerably better geared than my druid. Then I made my druid a moonkin and I do over 1100 dps during any instance. Pretty ridiculous if you ask me. My moonkin is always top on the dps meters.
I'm going to level in this fashion... DK to 70 then get rested xp, druid to 80, DK to 75, mage to 80, DK to 80. Warrior will take a back seat for now.
I had no problems with mana as frost with my mage. I mean with replenish and other new skills, it was difficult to run out of mana. Now my moonkin never drinks... I mean never. If I need to mana up, I use innervate. By the time I need mana again (if I need mana again), innervate is ready. The only time I would have to drink is if I innervated a healer during a fight, which sometimes I do for no reason at all. Sometimes I'll innervate a mage because I see them trying desperately to catch me in DPS and then they are OOM, lol...
My boomkin NEVER runs out of mana... NEVER.... over 10k hp buffed and 12k mana buffed. Moonkins are sick.
EDIT: Here is my mage's build. She rarely runs out of mana, if I drink it's just to top off before a boss fight.
http://www.wowarmory.com/character-s...ebeard&n=Payge