I think I need to make some videos of me actually losing Arena's.. yes it does happen!

Many of the really high ranked teams know what your capable of and play the waiting game or hide most of the match. It took over 2 hours last night for me to do 10 games to finish up the week on my high rated team. I went 9-1 but each game was at least 10 minutes, with a couple in the 25 minute range.

This whole blow up a target that comes within 36 yards is not doable. My tactics have evolved and it actually starts to break down even further in order to pull of wins.

Types of classes and what they can do:
Warriors go into defensive stance and chain spam Spell Reflect which will reflect multiple spells if they are thrown together, i.e. 4 Lightning Bolts. When I say chain spam, Spell Reflect is on a 10 second cooldown, but there is a way to exploit it currently by spamming /sit, allowing you to cast it every 5 seconds. In most cases if you see a warrior with a shield on, just ignore him - he's not doing any damage.
Mages have iceblock - every single one of them, they see the pain coming - they stop the pain.
Paladins have bubble, same scenario as mages.
Priests usually hug walls and almost 99% run around with Pain Suppression making your damage cry, and consuming your burst.
Shamans are what I like to kill first, their single grounding totem is the bane of your existence with synchronized attacks. I can't count how many times 1 well placed grounding totem has consumed 4 Lightning Bolts and 4 instant cast Chain Lightnings.. 8 spells into 1 totem, ugh!
Druids plays exceedingly defensive, and they can usually be ignored, their quick shifts make them tough to lock down long enough to get more than a Lightning Bolt off.
Hunters are able to pluck away at 41 yard > your 36, and have Feign Death to stop your casting abruptly. The good news is that is all they have - usually one of the first targets since they can't completely stop the damage, and usually one of the highest DPS in a match.
Warlock... warlock... every single one of them rolls around with Soul Link and a Fel Hunter giving them insane resists. No joke I've launched 2 Volleys of Lightning Bolts and 4 instant cast Chain Lightnings + 4 Earthshocks and the Warlock still had 30% health left. They are killable but you need to drop the pet first if you want to burst them down, usually not a good first target. I leave them for last as all they do is annoy - no real damage.
Rogues are currently the most Overpowered class against us at the moment, coming in the form of Cheat Death. Most don't view this skill as asinine but I don't see how you can't. The flavor of the month for Rogues is Shadow step which is very deep into the Subtlety tree, giving them Cheat Death. This ability is a GUARENTEED proc if they are going to die and negates the damage that would have done the killing blow while incoming damage for the next 3 seconds is reduced by 90-99% damage. So if the Rogue has 2000 HP and you hit him for 3000 damage, he does not die and is still at 2000 hp while also being practically unkillable for the next 3 seconds. It's also on a 1 minute cooldown!! Passive ability ftw..
Also the ever wonderful Cloak of Shadows which means 0 damage for 5 seconds on a 1 minute cooldown, and if somehow any of those are down within a 1 minute time frame they can just vanish and start over. I've had many teams run in, blow everything and then run away and let their cooldowns refresh.

Hopefully that gives a good reality perspective of what your up against. Now for the tactics on how to evolve past this.
1.You play on your terms and do not budge!
Blade's Edge Arena, you stay on the bridge and make them come to you. Providing an open surface where they cannot hide.
Ruins of Lordaeron, either take the middle tombstone over and own it - or set up camp in the front of your starting area.
Nagrand Arena, take over a pillar and hide/LoS if they carry a hunter, if no hunter you can utilize the cubby holes where the shadow sight orb spawns.
All these locations force them to fight you in an open field, it's in your realm - on your territory.
2. Be prepared to sit and wait!
Oh they know your packing the heat - and you can only imagine whats going on in their vent channel. Luckily your team consists of 1-2 players that have all the time in the world compared to 5 who can't be on all day long. They'll come to you.
3. Evolve - they find tactics to counter you, you find a counter of that counter!
Your probably wondering what my counter is?
You give em' the ole 1-2 punch! Set a focus for the target you want to kill, then select a different target that you also may want to take down. This way you are clearly showing who you want to take out, they will prep with pre-heals and Pain suppressions - the whole shabang to keep that player alive when they rush in.
You can soften up the first target by throwing a lightning bolt, maybe blowing an earthshock their way and then WAMMY hit your /target Focus macro so you swapped to your real desired kill and Boom shakalaka - they can do nothing about it. Their heals just landed on the wrong target and the target swap was way too fast for them to control. This ability in and of itself is the definition of good teams that are rated in the highest brackets out there, yet they will never ever ever be able to perform this type of maneuver the way we can.
Whew that was long, hopefully helps