Hearthpwn

If you've been looking for a fun off-meta deck that can hold its own against some of the top tier decks, look no further than a Naga Arcane Spell Hunter build!  I've seen people try to play the deck with the Wildseed package, but I find that dilutes the pool of spells that Arcane Quiver can choose from, and the Naga package slots into what the deck tries to do quite nicely.  I only play casually in the lower ranks, but I've been playing this deck since March of the Lich King released, and this deck can easily contest the board and win against other, more meta aggressive decks like Imp Curselock, Pure Paladin, and the (now-nerfed) Shockspitter Hunter.  I even managed to get the 12 win-streak achievement playing this deck on ladder, something I hadn't achieved before this despite playing on and off since Naxxramas.

This deck is a bit of a tempo deck with lots of burst potential in the mid-to-late game.  It plays very similarly to a Frost Death Knight deck - it similarly has that 'control-the-board-until-you-can-pop-off-with-spells' vibe.  You can control the board early with cheap Nagas and a big Eversong Portal, and then by the midgame you should have enough burst potential with big buffed Arcane Spells to take down your opponent.  A big Eversong Portal on curve can even win games on its own!  With Barak Kodobane, Conjured Arrow, and a couple of the other draw cards, you should have no issue keeping a large hand of spells to buff with Silvermoon Farstrider and your other spell damage cards.

For the Mulligan, you're looking for early-game tempo cards like Vicious Slitherspear, Halduron Brightwing, Rainbow Glowscale is okay to play for tempo, and potentially even Queen Azshara and Conch's Call against a slower deck.  Silvermoon Farstrider, Arcane Quiver and Conjured Arrow are similarly good keeps.  You want to send most of your Arcane spells back to the deck so that they can be buffed by Brightwing and Arcane Quiver.

There are probably some cards that could be swapped out to increase the deck's overall consistency, but I'm not sure what those cards are, outside of more Arcane/Naga support in the miniset/next expansion. 

Thanks for reading, and good luck!