PVE:

As an Elemental shaman in the pve end game, it's pretty hard to be competitive. It requires quite some experience and perfect understanding of the spec as opposed to other classes that are way more forgiving and still top meters. The rotation, as far as there is one, is very dynamic and you have to make choices all the time; which is a thing that I find fun, not everyone feels the same. I can see why you find it boring at lower levels when you only have a fraction of your abilities and required haste.

Back in ICC the quote: elemental is easy to play but hard to master is no longer true in my opinion. If you don't know what you are doing or make an error and your dps gets gimped a lot.

Destruction locks and shadow priests are topping dps meters at the moment. Shadow priest is one of those specs that I find really forgiving as I play it as an alt, though they are hard to master.

PVP

Elemental shaman is the spec that is in a terrible pvp state. There are so many things not working at the moment that it's unreal that blizz keeps changing other specs while they haven't made a single comment on elemental pvp. On top of that we got nerfed a lot in the latest patch (tremor totem change, purge, hex reduction, bloodlust being removed from arena). While those changes might have been necessary for other specs, it affects ele a lot. Any melee will sit on you and basically you have no way to get rid of them. You'll have to use your best offensive abilities (spiritwalkers grace & elemental mastery) for defensive matters. On top of that bloody warriors and rogues have more selfhealing we do. And haste is too low at the moment to get any casts off. Not to mention that many classes can lock us out completely cause of our nature school. There is a spec that works though (speccing deep into resto tree). I expect that ele will pickup as our haste /mastery will increase (i use for instance a pve trinket for pvp with a 2k mastery proc + the tol barad resistance one.

2x ele in bg is very good, 2x ele in arena is ok for your 5 weekly wins, but anything besides that ain't gonna happen when you face good players.

I don't know how boxable lock / priests are, but the combo works when solo played.