I´d like to emulate hermetic mages of the SR3 variety by using the rules for mentor spirits. The obvious solution would be the classic bonus to the linked spell group and spirit type, and a disadvantage to the opposite spirit.

But I´d like a more creative approach, giving a suggestion for a typical mindset (fire could either be offensive or warming, stone is calmth/strength), a bonus to spells with a fitting elemental effect, a fitting skill, and a disadvantage resulting from the mindset, not an oposite element.

Let the brainstorming begin. (This started a bit more specific and is for my girlfriend, so lets start with fire. And yeah, she´s a hot gamer chick.)

I'm sorry, but as a representative of the Gamers' Union we cannot currently brainstorm for you at this time. We first require a picture of said hot gamer chick girlfriend before negotiations can commence.

Security level "My eyes only", pending further notice. Awfully sorry.

I could offer not bringing Moon-Hawk his RAW back for considerably less than 200k...

now get to work.

Fire Elementalists:

Fire is the element of action and drive. Thus, fire elementalists are driven, active people. To these fire mages acting is more important than thinking, and planning is seen as an unneccesary evil. To them the "gut instinct" approach is the purest and most likely to be correct course of action. As such they often have trouble "switching gears" and are stubbornly devoted to a course of action once they have chosen it.

Give them a +2 bonus on fire spells, a +2 bonus to some sort of athletic skill (perhaps letting them choose any from the Athletics skill group). I was thinking they could get a -2 on the first action they take that diverges from what they were doing. For instance, if she is blasting people with manabolts she would suffer a -2 to casting an invisibility spell to escape.

Great start. I´d call that "aggressive fire".

Another one might be:

Warming Fire
Fire is also the warming fire of the sun, the driving strength of all life. The magician applies his mental control to the light inside things, healing them and changeing their form (think metalworks). Only if he gets ill-tempered will he turn on the heat too much.

Advantages: +2 dice to healing spells, +2 dice to Survival if temperature is a factor.
Disatvantages: May only ever learn combat spells with fire effect.