The Enchanted, Inc. question of the week was about the background of Rod and Owen. I've spent a bit of time imagining this. There are a few details that might come into play in a later book, but I think I can share most of that backstory without spoiling anything. Of course, anything not spelled out in a book is subject to change in later books if the story requires it (though I'm more likely to be influenced in later books by what I've already imagined).
Rod is about three years older than Owen. That's the kind of age difference that's just about meaningless when they're adults but that was a big deal in the beginning. A thirty-year-old (well, almost, as of the latest book) and a thirty-three-year-old are essentially peers. To a seven-year-old, a four-year-old is just a baby. Owen was about four when James and Gloria, his foster parents, took him in, and since they didn't have other kids of their own, they thought that it would help him to be around other kids, and Rod's parents were their friends and neighbors, so all the adults thought it would be a great idea to enlist Rod's help to look after this little boy who'd had a pretty rough life. At first, I could imagine Rod's reaction would have been along the lines of "But, Mooooommm! He's just a baby!" But then he would have come to kind of like having a littler kid think he was an awesome big kid. That's a big confidence boost that might have contributed to the swagger we see in Rod today.
In spite of the age difference, they would have ended up not being that far apart in school once Owen started school, since Owen is exceptionally bright and you don't want a wizard child to get bored, so he'd have been moved ahead in school until they were maybe one grade apart. Then they started gradually becoming real friends, though always with a bit of big brother/little brother element. Owen was a late bloomer who was a scrawny little kid with Coke-bottle glasses, so while they were in school, they were pretty much two of a kind, the kind of nerdy, brainy guys who spent their spare time working on their magic and who weren't the kind of guys the girls noticed. Around the time Rod went off to college, that was when Owen started filling out, grew into his bone structure and got contact lenses, so that was when Rod reinvented himself with the handsome illusion as a way of keeping up with his best friend. I imagine it would be tough to be suddenly eclipsed by your "little brother" who had been on a par with him, and that illusion allowed him to feel more like an equal.
As for the other question that was asked about the founding of MSI in Arthurian days, I haven't thought much about it in any detail because it hasn't mattered for a book. Yet. But now ...