I read the the following books, which gave me one way or another an Ars Magica feeling (or some really good ideas for gaming sessions) :
from Naomi Novik Uprooted (the main character becomes the apprentice of an eccentric wizard's called "The Dragon", takes place near an enchanted forest full of dark faeries...) Spinning Silver : some kind of lord of the faeries of winter giving what seems to be impossible tasks to the main character
From T. Kingfisher, mostly faerie stories, some are also good mage's stories Bryony And Roses, an alternative take on Beauty and the Beast The Raven and the Reindeer, the main character go on a quest to save her friend who got kidnapped by the queen of winter Summer in Orcus, Baba Yaga, bird people, talking wolves, magic cheese... Nettle & Bone, faerie midnight market, another set of seemingly impossible tasks, helpful witches The Seventh Bride, the main character becomes the bride of a powerful lord which is also a wizard A Wizard's Guide To Defensive Baking, after reading this I wanted to play a mage with a minor magical focus in baking. So many good ideas Minor Mage,
So one of the podcasts that I listen to is called the Splatbook and 2 of their last 3 episodes have been on the topic of appendix N, discussing media that influences/d their gaming.
Seventh Son of a Seventh Son. To me the feel of the opening minutes of this film just scream "Ars Magica". YMMV based on your preferred edition.
The old classic Dragon Slayer. An isolated covenant in the final (?) throes of Winter has to get involved in the outside world for the first time in who knows how long and there are consequences.
We actually set out to play Kragenmoor's history as our own covenant circa 1999 but the saga got disrupted by the SG (self) moving across the country.
That's a particularly roundabout way of getting inspiration for a saga! The different PLL spin-offs have made excellent inspiration for Monster Hearts (a game about teenage monsters) around my gaming table, but I never thought it would work for Ars.