Canis said:Instead of taking the "blood of dragons makes a sorceror" angle, your sorceror could believe he has the blood of a Djinni or Efreeti. Preferentially go after the spell-like abilities of his suspected ancestor and appropriate elemental spells. He would, of course, wield a scimitar and wear a vest...
Considering you have a paladin and a cleric in your party, I would do with the Chaotic Good Djinni over the Efreeti (how kindly would your paladin take to you running around claiming descent from an evil outsider?). You could use most or all of the list humble minion provided for a storm mage, and it's more interesting than yet another fire mage.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.