ehum, for mages, IF you go fire spec (judging by spellfire set), you should go for spellstrike and not battlecast, if you go into FB. Spellstrike = PVE CRIT, battlecast = PVP STA
with some decent gear, not real 25 man gear and almost no kharazhan epic, quite few blues and no epics, but spellfire set, you should crit fire 6000+. at least thats what i did.
My frost now crits for 6000+ (WEEHA), and thats why i respecced. fire is nice and wonderful, but with your spellfire set you will lack the mana do raid decently, considering you waste double the mana and 0.5 more cast time to get decent damage. for 5-10 men it shoudl be enough, even though zul aman will also be tough.
i have a tough time with rogues and locks, VERY tough, and that is considering that i dish out around 1100 DPs without additional potions. but i can hold for a long long time with frost. And since dead and me "know" we can be #1 dps on bosses or trashs respectively, well, we finally kick back. not gonna mke effort again until hijal / BT.
IF you would consider switching gear, you might get first. making 6th with the gear you mention (dont know your other pieces) lets me assume your raid has average output at best. you couls get them easy. i strongly suggest to switch gloves. spellfire is piss. its good when you have no raid gear yet. get T4 gloves or T5 and enchant T4 with +DAM and T5 with +HIT (they dont have). +hit is the value all of you other mages forget. wasting 400+ mana from you probably not more than 8000-9000 mana pool (buffed) and 3.0 seconds for getting a resist is a HUGE loss in dps. imagine it would have been a crit...... 15-16% total +hit is what you want (including talents). starting from 13% you will notice the differnece, even if your DAM / CRIT is lower than other mages. they get resists, you don't. on top of it, a small amount of +hit is factored into +penetration, yet not dpisplayed by blizzard. (confirmed by a blue post), so your spells land with slightly higher DAM as well.
i'll let you play your mage the way you like. just thought by reading your post you could need some pointers.
note i was fire until recently.
arcane frost is the absolute kick now with T5 gear on me, but i have to admit that i lacks some crowd control and survivability , for the dps. yet DPS is sick sick sick.
keep up. will post screens