Trust me mate, what you re planing to do is a huge mistake, and a waste of time. Ive played shamans on all versions and expansions, and what I can tell you, I tried all possible gear/set combinations and talent builds, and no mather what you do, on 1.12.1 you will always suck as a dps compared to rogues and warriors as Enh, or mages and warlocks as Ele.
If you want to do some serious raiding, just go to restoration, and roll for elemental items also, to PvP with while raids are on cooldown. I was respecing twice a week back in ED. FTW!:biggrin: The 100 gold a week was worth tho, zaping alliance is fun.
Practicly, the only reason for a raid to bring an elemental shaman is if the shaman and the raid leader are very good irl or ingame friends, or the raid is heavily overgeared and they can clear even with 1 less DPS.
On the other hand, bringing ele/enh shamans, ballance/feral druids, arms warriors or retri paladins to a progression raid is a suicide.