**moved my post here**
First and foremost.. your spec is... subpar at best.
Talent Calculator - World of Warcraft
that is a spec I just threw together. It doesnt have imp strength of earth totems, but it has unleashed rage. You can alternate the points as you see fit. One of the most important things as an enhancement shaman is this.
You run frostbrand weapon on your offhand, windfury on your main. BOTH weapons need to be slow weapons. 2.4 - 2.6 in speed. You need to keep lightning shield up at all times. Also, you need to make sure you keep magma totem down. It does a HEFTY amount of damage. This was something out enhancement shaman always seemed to not notice at first. Granted, on some fights its just pointless to try (such as grobulus) but on almost every fight in naxx, magma totem needs to be down.
As an enhancement shaman you do not stack spell power.. period. You get SP from your ap. One of the best things to get at first will be hit rating and expertise rating. They hinder your dps alot by missing/dodging windfurys and your normalized attacks.
Also, reading a bit more, I don't know which you're supposed to run on your offhand these days weapon enhancement wise.. Either flametongue or frostbrand. You'll have to ask someone else for that advice. This should give you some steps in the right direction though.
Also, when maelstrom weapon procs.. if chain lightning is off cd, use it over lightning bolt.. it does more damage (or did, they may have nerfed it too. You'll have to check into it)