The points in Unrelenting Storms, Elemental Warding, and Nature's Grace are mostly wasted imo, and Healing Grace and Convection could be better put to use. I'd think something like
this would be much better, you get double crit damage, more damage from Lbolt, 10% more crit, and all you lose it a tiny amount of regen, reduced damage that you'll never be taking in the first place, and Nature's Guardian that should never be proccing anywho. I'd probably take the points out of Healing Grace and drop them into Lightning Mastery as well, or more likely, into Healing Way.
That said, I'd be reluctant to take anyone sepcced that way into anything beyond a few of the easier heroics, unless they had really, really good gear. Even then, serious (timed) ZA and any 25-mans would be out of the question unless the rest of the raid was already incredibly geared.