For a while I've been experimenting with trying to make magi a little less powerful for whatever reason... In my case, trying to fit magi a little more smoothly into the rest of Mythic Europe. I've played around with the Arts as Abilities and a number of other house rules, all with this goal in mind. I've finally landed on a simple set of house rules that, I think, will achieve that goal... and I'm hoping the charming folks here one the forums can rip them apart for me.
The rules are simple. Magic and arts advancement are unchanged. Instead, the character creation rules for Hermetic Apprenticeship and After Apprenticeship are changed. Instead of receiving 240 exp and 120 levels of spells for apprenticeship, magi recieve normal exp for their age, plus 50 exp in Arts and 50 levels of spells (this also assumes a shorter apprenticeship... more on the lines of basic academic or clerical education). Additionally, magi recieve only 2 free seasons after apprenticeship (and thus only 15 exp per year if creating a magus out of apprenticeship) and magi must take a Social Status virtue in addition to Magus. Essentially, magi are assumed to live in the world and support themselves much like everyone else.
Thoughts, comments, opinions, etc... and especially, if anyone is feeling bored/ambitious/really helpful, I'd love to see how someone who isn't me or one of my players would make a magus character using these rules.