http://imgur.com/jpFlkZd
This is my brew to counter Hunters, I've been adjusting it over the last couple of days, the first version had Arcane Missiles and Acolytes, but I swapped Missiles for a second Pyro and Sylvanas, and Acolytes became AI for a faster draw and synergy with Mana Wyrm. I don't know what changes I would make, other than Thalnos over Geomancer and probably Harrison over Ooze, those are just because I don't have the cards. Two Polys + Rag and Sylvanas and decent midrange minions make it solid against control decks (mostly been playing against Warriors, Priests, and Ramp Druids of those), Warlocks are hard matchups because you get buried in card draw, but I think this deck is favored against all Hunters. You have Mana Wyrms, Chows, and Pyros to control their early game, and if you stabilize after 4-5 turns with above 20 health, then you probably win comfortably. Because of the Fireballs and Frostbolts, this deck does have a lot of burst potential, that helps against Control decks and gives you an out against Hunters if you stabilized at a lower health. Polymorph handles Highmane and Belcher can give you some security. Right now, I'm at rank 2, so I'm hoping to push to Legend over the next few days.
TL;DR Arcane Explosion is actually a fantastic card.
Arcane Explosion is really mediocre. It's awful in every matchup barring Hunter as a two-of, and you don't see it enough in Hunter matchups for it to matter as a one-of. I tried it out when I was pissed at Hunter too, and it was just kind of fucking awful. Here's a control Mage list I've been running that actually does pretty well against Hunter despite the fucking existence of Flare:
so basically you win control matchups by pulling your legendaries, Molten Giant, or occasionally even Acolyte and Water Elemental (both good in Warrior matchups) and then simply out-value-ing them with your tons of late game that can't come close to yours. When I was modifying this list, I thought about what my bane was as Hunter, and I pretty much realized it was Zombie Chow, regardless of the deck running them. Lots of people run Undertaker synergy or Mana Wyrm for control Mage early game, but I think double Chow works really well for it. against Hunter, you'll usually have to test the waters on Flares with Duplicate or just pray they don't have it, and as long as you can control the early game, you can easily win the late game. Molten Giants and Belchers are huge too. I think I actually cut the Acolytes earlier today because I was seeing mostly control decks that would beat me by silencing my Acolytes or limiting me to one draw with them, and Arcane Intellect was just much better there. But if you're mostly seeing Hunter, Acolytes are better. They're awful vs. Zoo though because early they have Flame Imp, Knife Juggler, Abusive Sergeast, Dire Wolf Alpha, etc. to deny you your multiple draws. I also tried double Ice Barrier over Earthen Rings, but I found I appreciated the flexibility of being able to heal my minions, having fewer dead draws in the early game, and just having another body on board. Plus, you can Duplicate them against aggro.
Also Hunters usually run double Bow with three Traps, though it's flexible. I've mostly been seeing double Freezing/one Snake, but occasionally I'll run into a stray Explosive or face Hunters with just two Explosives. Even if they don't pull a Trap reveal with Bow up, it's still six damage for three mana, which is good enough to run double. Plus, no Buzzard combos to clog your hand with traps and the second Bow, so they rarely clash anymore.
Also my Mage list is really expensive and not the best at beating Hunter anyways (but it's really fun if you have the cards, highly recommend), so if you're looking for budget anti-Hunter, fight fire with fire and run face Hunter. You have basically identical early game, but you close out games much more quickly with chargers and forcing them to trade at the risk of them dying rather than vice-versa. Face Hunter has me up to I think rank 2/4 stars right now, and I've played maybe 5 hours past rank 15. Only bad parts are that it's weaker against Handlock (my winrate is still about 65% against them tho) and Priest/Warrior if you draw poorly.