PvE-wise, I’m not well versed with how strong they are but according to DPS rankings, even tank shaman is out dpsing other damage specs. (Not sure if this is the average shaman player statistic but take this for a grain of salt). PvP though, they are steam rolling. They need a nerf, bad. There’s no way that you’re telling me they can 1.5k+ burst for free every lava burst cd. Enhance just hits like a truck. Apparently, they also have ridiculous amount of health (tankyness). Utility is off the charts with the totem spam and purging, which also results in you dying immediately from losing personal/defensive buffs. IE: Fort/Inner focus, Ice armor, Shield, etc etc. I’m not asking them to be useless, just tune them down a bit. Just like balance druid, their starsurge got nerfed but they still are a very good class (in terms of pvp). The fact that they can just walk in to people with no fear or any thought into the engagement says enough.
TLDR: Tune them down, they are steamrolling pvp matches like its nothing.