This is really rather off-topic, but Charles' designation of Laetitia Laureata as a Mary Sue carried us into a conversation about whether or not she is one, what would suffice to qualify an RPG character as a Sue anyway, and so forth, which in turn led us into the age-old "What the hell IS a Mary Sue?" discussion —and anyway, so I thought perhaps these links might be of interest.

Mhari's Mary Sue Classification page is the classic Sueologists' resource.

Anadrel has begun working up an even more elaborate schema of Sues. Sadly, it's still very much incomplete. Even more sadly, it's hosted on the wretched, wretched Lycos/Angelfire.

If you can cope with Angelfire, though, what Anadrel has so far is pretty good for a laugh. (I am particularly fond of her taxonomic break-downs of puella subcanonica.)

The opening pages of her Guide to the Sues in the Field are also quite enjoyable, particularly the Introduction, which outlines some of the more popular theories On the Origin of the Species.

Anyway, as far as I'm concerned, background mage characters for the Known World are all pretty much canon characters, and therefore really can't, properly speaking, be Sues 'tall. (We'll just leave Laurel K. Hamilton and Anne McCaffrey out of this equation for now, though, shall we?)

Otherwise, though, I'd cast my vote for Coturnix and Caesius as the most Mary Sueish magi in the history of the Order. They're certainly both far worse on that count than dear Laetitia.