My concepts:
1 A scion of house Orien (or Lyrandar, if we need a pilot) who doesn't get along with his family very well. He went behind their backs and signed up for the Aundarian Army to impress some local girls. All of his buddies he signed up with died, but he managed to survive. He showed some Arcane Talent early on, so he was recruited into one of Aundair's many combat-wizard agencies.
If Orien (Daen d'Orien) Though his early training is in marshal pursuits, his skill as a wizard was apparant very early on. He has been trained in some of the finest Orien and Aundarian travel-magic, and has learned a decent variety of spells designed to be cast in armor. He is a very mobile combatant and uses his magic tactically to either get himself where trouble is and fight his way out of it, or fight his way into trouble, and then leave quickly when the time to be scarce arrives. The fact that he manifested a mark while in the service troubled his family, and while his involvement didn't overtly break the non-involvement laws of the Dragonmarked houses, they are sometimes unsure where his loyalty really is. His comrades in arms know he is loyal as he has gotten them into and out of a number of VERY sticky situations again and again. His DM house background means he's familiar with politics, all the same, he sees himself as little more than a simple soldier whose first loyalty is to Aundair, second loyalty is to his fellow soldiers, and his House and own self fall somewhat lower on the list. As such, he will never rise very high in House Orien. (his build would probably be a fighter 1/Wizard X. If one day we got PRCs, he'd likely pursue Wayfarer Guide from Complete Arcane as an ancient collection of House Orien Travel Magic secrets.)
If Lyrandar (Sir Sarelo d'Lyrandar) Seeing the sacrifice so many of his friends made in the name of Aundair, and bolstered by the atrocities other nations commited against the country he served, he was knighted a Cavalier in Aundair's service, hoping, eventually, to become one of the few, the proud, the Knight Phantoms. Along the way, however, he manifests a dragon mark, and his nation finds a better use for him--as the pilot of an airship. Still hopeful of being granted Knight Phantom training, he serves his country in the best way he knows how, by spell and by sword. He'd probably have only met any of the other characters before they worked together as a unit if they are cavalry/dragoon type units. Otherwise, he first met them when he was brought on to pilot the Airship in Aundair's service. He tends to be forth-wright with his dealings, which means that he is rarely expected to take the lead in most of the "black-ops" work they are expected to do. However, when it comes to diplomacy, pretending to be a reputable bunch of merchants/traders/explorers, or a straight-up fight, Sir Sarelo is your man. (His build is very open-ended. Knight 2/Wizard 5, Knight 2/Sorcerer 6, and Knight 2/Bard 7 (if you'll allow non-lawful bards) before pursuing Knight Phantom (if allowed) and/or Dragon-marked Heir (if knight phantom is not o.k.) are all very appealing to me. Replacing any of those builds with Fighter 1 in place of Knight 2 would also make me plenty happy.)