I'm happy to see lots of mage teams running around now :)
I have got several questions about "what now?" when people ding their teams to 85, and they're looking forward to access Bastion of Twilight and Firelands epics.
There is no superfast way to do this.
When I dinged my mages to 85, my item levels were like 285-300 on each mage (gear from quest rewards). Then I moved to non-heroic Cata dungeons for 333 loot off from the bosses. Then I started to grind reputations up with some factions with 359 exalted rewards. I equipped faction tabards and farmed mostly in The Lost City of Tol'vir heroic for world drop epics and for the faction reputation. I did this quite a long time (a month or so) before I entered TBoT10 just for the lulz and my goal was just to kill one mob and hoping he had an epic on his loot table..
TBoT10 trash as low geared (300-333) is not fast. I used to farm 4 first mobs in that instance. I used to sheep melee, healer and hunter and then bursted down the one mob which can't be sheeped (with mirror images tanking). When the first mob was dead, I waited for mirror images cooldown while kept the other 3 mobs sheeped, then nuked down the healer one while interrupting their spells (round-robin counterspell), then waited mirror images cooldown again and bursted down the melee one (mirror images tanking him as well).. Then there was only the Twilight Crossfire ranged mob left, I used invisibility on all toons, and the trash pack respawned and I did all of this again, and again, and again..
Later I realized that I don't have to wait the mirror images cooldown, just needed to have round-robin on frost nova and talented cone of cold, so I could root the rootable mobs while nuking them and rerooting and they never reached my team.. So there I farmed some 359 weapons and gear for my little soldiers.. and each epic I got, the easier the job was..
If you can afford leveling like 5 engineers, then I'd suggest doing that for the 359 helm, since it's pure awesome.
Head: Lightweight Bio-Optic Killshades (Engineering)
Neck: Nightweaver's Amulet (Firelands dailies)
Shoulders: Jan'alari's Spaulders (Jan'alai heroic drop in ZA, not easy, better to farm 346 hc shoulders)
Cape: Rippling Flamewrath Drape (Firelands dailies)
Chest: Firelord's Robes (Justice Points)
Bracers: Bracers of the Dark Pool (Bastion of Twilight drop, 359 BoE)
Hands: Firelord's Gloves (Justice Points)
Belt: Embereye Belt (Firelands reputation - Honored, or tailoring 359 BoE ones)
Pants: Firelord's Leggings (Justice Pointsm or tailoring 359 BoE ones)
Feet: Desert Walker Sandals (Ramkahen - Exalted)
Ring1: Band of Secret Names (Justice Points)
Ring2: Lavishly Jeweled Ring (Deadmines heroic boss drop, need a real party for last boss)
Trinket1: Darkmoon Card: Volcano (crafted 359 BoE)
Trinket2: Soul Casket (Justice Points)
Weapon: Spire of Scarlet Pain (FL trash, also tBoT10 trash drops 359 staves)
Wand: Touch of Discord (ZG heroic bosses)
So here's something to aim for. If you feel like farming Justice Points or Baradin Hold or just gold, that's one sort of shortcut. If you ding 85 and got 275-300 item level, and you want to go cata heroics for 346 loot right away, I'm afraid that's not gonna happen like that.
Better to spend some gold on (crafted) BoE 359 stuff.
Also remember to cap your hit to 6% and haste to around 15%, because that's all you going to need.