It does look like Orphan is the winning option.
Please note that the cities guard their Lighthouses, and have a general compact not to allow orphans from other cities into their own. While you can enter your own City's Lighthouse, or travel to an unclaimed one, picking Rosolin will lock out out of the Yellow and Green Lighthouses, picking Everett will lock you out of the Red and Yellow Lighthouses, and picking Madalgia will lock you out of the Red and Green Lighthouses. This will not effect you if you happen to somehow enter a second Lighthouse as a mage.
This is to pare down the choices a little before you pick a first school of magic, rather than simply presenting eighteen overly complex choices.
The footsteps came back, and you quickly hid the book away once more as the door swung open. Father Matthias stood there, shaking his head.
"I know you like to read, but come out! Listen to the sermon, speak to your fellows. After all, this is the greatest city in the world! This is..."
[ ] Rosolin, City of Ten Thousand Bows
Rosolin is the smallest of the Three Cities, boasting a population of a mere thirty thousand. When the population rises much above this, the Darkling raids intensify, and if it were to hit as many as thirty-five, the city would face a siege of tremendous power. As such, the young in the city who do not earn a place to stay are sent to the nearest Lighthouse, where most die. On occasion, one travels across the Shadowlands to the Violet Lighthouse, and returns with other powers.
Being so distant from the other two Cities, and so close to the Shadowlands means Rosolin is poor and small, but the Longshots and Breathtakers who defend its walls are without peer, and it is rare a raid does any real damage.
Living in Rosolin gains you magical knowledge regarding Longshots, Breathtakers, and Mindscours. Archery magic, air magic, and mind magic, respectively. This will enable you to better combat these mages, and you will be able to learn some useful spells if you happen to join one of these schools of magic. You will not be able to enter the Green or Yellow Lighthouses at first.
[ ] Everett, City of Eternal Green
Everett is the most defensible of the three cities. The Green Lighthouse brings Alchemists, who concoct explosives, healing flasks and the like, trading with the other Cities and with the surrounding countryside. The Vineweavers of Everett grow great plant walls, and fruits fall from the many trees grown within its gentle embrace. If the explosives and plants fail, then the Coldhands of Everett create great spears and blades of ice, driving the Darklings back as the last line of defense.
Safer than Roslin, Everett supports a population of forty-five thousand, though it faces many more raids as a result. At fifty thousand, it faces sieges and the like, and sends its orphans and unneeded youngsters to the Green Lighthouse, though some choose to strike off on their own, and enter the Blue.
Living in Rosolin gains you magical knowledge regarding Alchemists, Vineweavers, and Coldhands. Concoction magic, plant magic, and ice magic respectively. This will enable you to better combat these mages, and you will be able to learn some useful spells if you happen to join one of these schools of magic. You will not be able to enter the Red or Yellow Lighthouses at first.
[ ] Madalgia, City of the Three Trade Walls
Truly the largest of the Three Cities, Madalgia has a population of seventy thousand. Its distance from the Shadowlands allows it to support this, and its position between the other two Cities sees it trade with the other two, as well as send expeditions into the Pit for Artifacts. By far the richest, Madalgia often suffers from raids and even sieges.
However, it has perhaps the most useful magics. The Shaderunners do not defend the city, but slip between villagers and cities, carrying messages and useful Artifacts, trading in things the cities need from one another. The Spellthieves travel with them, able to steal (though more often pay for) useful magical effects that they can bring to bear for the city's defense later on, and the Glimpses peer into the immediate future, ensuring any attack is deflected by the city's mundane forces. However, with the stealth of the Shaderunners, Madalgia is able to better enter the Pit than any other city, and uses Artifacts to defend their walls, as well as sneaking groups of aspirants to the Orange Lighthousee.
Living in Madalgia gains you magical knowledge regarding Shaderunners, Spellthieves, and Glimpses. Stealth magic, effect-appropriating magic (a Spellthief can absorb and store a magical effect and use it later, though this requires another mage to cast for them), and precognition magic (certainly not Worm-level though) respectively. This will enable you to better combat these mages, and you will be able to learn some useful spells if you happen to join one of these schools of magic. You will not be able to enter the Green or Red Lighthouses at first.