What do you do with your mage, do you raid? do you have hopes of raiding? That could make a difference what you want. I'm going to give my input under the assumption you want to be raiding.
When it comes to stats.
1. Spell Hit till capped (fire cap is around 142ish?)
2. Spell dmg
3. Spell Crit
4. Spell Haste
Thats the way i prioritize my fire gear, many theory crafters put spell haste above spell dmg. Spell haste is great, but make sure you not losing to much of another stat to get it in there.
As for Gemming. Gemming is a good way to help a gimping stat. you have mostly +hit and +stam in your gemming. For a Mage, i would try to lean to +hit till capped, then +dmg. The stam is nice, considering crafted gear carry's very little stamina, but you really could use more +dmg.
yellow: 4crit/5dmg or the 4hit/5dmg
blue: 5dmg/6stam
Red: 9dmg
i only follow socket colors when the set bonus is worth it in dmg, usualy +5splldmg its worth it to follow the gem colors. Dont forget though, your not at spell hit, as you get more gear that carries spell hit, you can think to replace the gems you do have for more dmg.
Also the 2/48/11 spec though good for raiding, requires a considerable amount of spell damage to sit on. You might see in increase in your damage output, if you switched to an arcane/fire build Untill you get closer to 800spell dmg with gear.
Keep running those H.MgT's if possible they carry a few upgrades for you in there, Main Hand, shoulders. and i would definetly reccomend getting the new badge ring.