ok, I'm going to assume for a moment that Elemental Focus will NOT benefit healing spells, since most of the builds so far have been based on it doing so. Of course, this will be a raid build as well (focused on the 25-man end of things). My result comes to:
War Pirate :: Shaman WotLK Alpha Talent Tree
...well, a few of those points are debatable, but not all THAT many. Sum of it is that I can NOT find any way to justify the 5 points it would take for me to get Nature's Guardian, unless it became apparent that i would never be casting any actual heal other than Chain Heal (a remote possibility, but only in some VERY screwy 25-man environments. If it comes to that, then:
War Pirate :: Shaman WotLK Alpha Talent Tree
Like I said, screwy as a lightbulb convention, but it could (theoretically) happen.
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I've also been looking at things from a PvP perspective recently, and THAT is just as hard as the PvE side of things. It's astounding how many points shift. I'm assuming moderately high-level play, where foes will get rid of your Tide with alacrity.
War Pirate :: Shaman WotLK Alpha Talent Tree