So,
Balance in Ars Magica. We all want to create NPCs whose actual capabilities correspond to who they are supposed to be, whose actions correspond to their motivations, and then we hit the AM rules, and blam! That archdemon or daimon that is supposed to represent some great power has a few tricks but doesn't quite represent the power and is blown away easily by magi with surprisingly few decades under their belts, and some saved up vis. Oops! It takes a great deal of system mastery for this kind of thing not to happen, and some of that mastery involves simply ignoring the rules and doing something else.
Maybe I should use a different word, like congruence or aptness.
In a similar vein, there is absolutely nothing on Fibonacci's character sheet to suggest that he is any different from any of the many, many mathematical non-entities who held prestigious positions at respected institutions... competent but utterly forgettable. So there you are, and you want to create your own Fibonacci but also want to use the rules, because otherwise why not go systemless and save a whole lot of number crunching and chart lookups? That's not about classical game balance, of course, because Fibonacci is probably a trivial combat encounter.
But
is difficult to actually achieve. Heck, even with system mastery, powerful characters can take weeks to write up.
Sometimes it isn't about game mechanics at all. Hmm. Balance, motivation, rules, mechanics, implications. Let's talk a bit about Marko's long-running Andorra saga. I played a bit-part NPC in that saga for a few weeks....
First the easy part, which is game mechanics: Marko decided that RoP:M rules for creating dragonkind did not do justice even to wimpy dragons, so he doubled the amount of quality points they receive. That did make a difference. System mastery ftw. He then sent me 3 drakes he had sketched up to play, and to modify their character sheets to suit what I wanted to do with them, around Might 25-30 iirc. Not shabby with doubled points. But far from optimized, and they needed to be at their very best to last more than a few seconds against the magi of Andorra. They were supposed to go down, of course, because it was a vis hunt. (Note the need for creating a balanced encounter: The magi are perfectly able to find this kind of encounter, so using the rules better allow it.)
Still, I was allowed to modify the characters to suit, and play them as I like (more in part 2). So I modified the drakes, was asked not to use certain rules that made their powers better but which Marko felt uncomfortable about aesthetically, and I reverted the offending changes. Drakes improved, but still not a real combat challenge. That's fine, playing cannon fodder for some handfuls of posts can be fun too. I don't know what Marko intended, but I saw the numbers and knew. Ok.
Motivation and system effects: So here I am, with modified drakes, who at least have perception enough to see what's coming, and the drake who notices has Intelligence. So here you are, a magical drake. In editions past, you ate virgins and held villages in thrall and mocked knights... but in AM5 that's only good for faerie dragons. Real dragons get nothing from this: They need to eat vis, and lots of it. Intelligent dragons or drakes surely realize this. If you act like a storybook dragon, you will starve. So my intelligent drake didn't want to starve. He also didn't like the idea of getting killed by the powerful wizards who periodically come down from their lair to kill things and suck out their nutrients (ie vis.) So rather than ambush the magi (and their grogs) and then get killed (bad) along with his siblings (they're... useful, and it's easy to trust those you understand (fellow drakes) and who are dumber than you), he talked with the magi. And talked, and talked. And no more vis hunt.
Not a bad story in itself, yes, but.... drakes are supposed to act like drakes, and the rules should support this. This is a second kind of difficulty with AM rules, and maybe more important. My idea of rules being broken is when the rules do not support the fluff. The drake saved his life, and his brothers, by playing motivations that aligned with the rules, not the fluff. Not a failure of game at all, I had fun, at least, (playing 3 different flavors of nasty yet not evil,) but a drake played according to the way the world works according to game mechanics is very different from one played according to 'fluff'. It's sort of like playing an rpg "Pirates of the Caribbean" in which the pirates go legit because the rules make that more efficient, and because character motivations will lead them to take advantage of that efficiency, completely IC. The weirdness of "Pirates of the Caribbean on Wall Street" might make for a diverting amusement, even a better game... but not the game intended, with congruent motivations and actions that simply don't belong.
Just musing,
Ken