I made a great big huge response to this, but I'm deleting it and going to respond better when I'm not at work.
But based on your answers, I gotta be honest with you...
Don't take this as an insult, but have you even played rated arena? Are you level 70? And if so, how deep into the arena ladder (rating) have you gotten?
You have some very wrong ideas about hunters, first of all... and you don't seem to know much about the current situation regarding healers in the arena. Let's face it, they're MVP in 1800+ rating.
And just as a quick FYI, a hunter cannot autoshoot and move. No healer stands in the open, we hardly get to autoshoot. Also, heres a fact for you: The smallest pillar in the arena to date with a healer running circles against it would require the hunter to reach exactly TWICE the healers speed to run circles with him and still hit him at minimum range to dead zone (BARE minimum, if you get back any you'd need to run more than twice as fast). That is epic mount speed against an unsnared target. There is no situation ever that would allow a hunter to maintain twice the speed of his target. Even if I could shoot you with wing clip and run free as a bird with cheetah without dazes, I still couldn't keep in LoS. Think I got time to autoshoot? Not really.
Are there ways around it? Yeah, there are. I can snare you and run along the pillar with you and then break off directly opposite from you than the pillar, this allows me a few seconds of shooting. It takes a while to do though, plenty of time for you to cast heal while im dead zoning myself to get past you.
Am I saying they're overpowered? No. The LoS brings strategy to it, it really does. But right now the advantage lies with the healers.
Theres a reason blizzard stated in an interview theyre going to give hunters, for example, an ability to help deal with healers. Mortal Shot was mentioned in an interview by a dev recently (source: worldofraids.com).
Trust me, another class with mortal strike or a 5 min cooldown on death knights negating a single targets heals for a short duration aint gunna break your class. It'll give other classes options to beat you rather than lucky burst or stun/silence locks, but you'll still be the powerhouse arena match definer that healers are. You just may have to do more than run around a pillar to accomplish it. Besides, imagine what retarded things you'll get at level 80.