I mean, it seems to be intended to limit their ability to cast the same magic again and again. Which would make for boring combat and may break the setting. But - magi can do just that, casting magic again and again. Why can't creatures simply use the same basic mechanics as magi to "cast" their Powers?
Makes more sense for the earth elemental to be able to move earth at will, rather than a few times per day. "Times per day" is a holdover from D&D days, that doesn't fit how magic works in Ars Magica.
I'd suggest simply allowing creatures to activate powes of Level up to (Might - 10) for free, and have higher-level powers cost one Fatigue level or some similar price. Maybe throw in a line that repeated use of a power may require Fatigue rolls (much like repeated casting of low-level spells might).
It's closer to how Hermetic magic works, and is much easier to SG than micromanaging Might Points (and on TOP of fatigue and wounds, and often Might Score, too).
Spontaneous magic ("Focus Power" magical qualities) count as twice their level, and up to level 25 (x 2 = 50).
Worth noting, in the right environs a creature can recover its Might very quickly, meaning that even high-cost powers are less "times per/day" and more "every x hours/minutes", which tracks - having Might means you are, to a certain extent, unearthly, and it tracks then that a creature must, effectively, bring some magic with it into our world, then retreat to(wards) its Realm to gather some more. And the more that it uses its magic, the sooner it must retreat. It ties into the non-infinite nature of magic, and why mages are special - they've effectively cracked the code and have a much less finite amount of magic than basically anyone else.
I agree that the bookkeeping can grow tedious if you're in a tactics-and-points heavy game though. Tweaks and/or homebrews that give a character a signature thing that they use as an Ability might help - after all, something like Enchanting Music isn't mage/Gifted specific, and doesn't burn though fatigue. If you want an Earth Elemental whose whole thing is moving earth around, you could give it an Ability that gives it telekinesis (but only affecting earth/dirt/sand/stones), with bigger/more earth being a higher ease factor.
I like the current system because I have complete freedom to design a power that costs 0 points and has penetration equal to the creature’s Might, or I can let it keep its Might cost and reduce the power’s penetration. If I want the dragon to have a fire breath that murders all mundanes but leaves magi alone I just let it keep its high Might cost and now the fire can’t penetrate Parma. It’s a very flexible system. Not broken, don’t need fixing.
Well, the current rules allow changing the Penetration of the power irrespective of its cost, at least for Magical creatures. Presumably you would have similar ones under this system - you could take an Improved Penetration magical quality to increase penetration to beyond (Might - Level), or a Reduced Cost that lowers the Fatigue cost, or maybe even Inferiorities for their reverse.
By default, however, in the current system your cost in Might Points is Level/5, and your penetration is (Might - Level). In my suggestion, the default would be the same penetration, but the cost would be either zero (for Leve < Might - 10) or one Fatigue level (for higher Level effects). That's the major change. Variations can then be built on top of that.
It did always feel off to me. I also dislike how awkward it makes ritual power -- Especially because its so ambiguous "This lost Might may return over time, at the storyguide’s discretion, but at a much slower rate than recovering lost Might Points", and then they need something like Vis Mastery to make it viable. It gets worse if you compre them to non-hermetic tradtions; many have more vis efficent ways such as soquotron sorcery and hyperborean magi.
I houseruled it to change it so might points are both vis and fatigue, and might score is casting total. Its technically more complicated, but uses the same math as magi so its very familair and less burdensome IMO.
All beings of might have no faitgue levels, use might points as fatigue, and effectivley have Life Boost for thier powers and can thus spend one point of Might to boost casting total, and thereby penetration, by five.
Might is essentially a being's casting total.
Might point costs are reduced to MAX(Magnitutde(Power Level - Might score), 0); Penetration = Might Score + 5xMight cost - Power Level + Penetration bonuses for power master or penetration ability.
This is essentially just using The life boost to boost a too powerful ability untill your able to cast it.
You cannot use a power with a negative penetration. Unlike magi, you don't get the -1- -10 where it goes off with negligable penetration and a fatigue level.
Greater power gives 75 levels of powers. This is to account for not getting the 25 levels of reduced might cost.
Focus power's levels are doubled for the purpose of calculating penetration. Just treat it as Sponting.
Might recovers at a rate of 1/10 might score per year rounded up, if they arent suffering from accilmation or deprivation.
Improved recovery turns this into per season. Reduced recovery requries reduces it to 1 might point per year. Stack with recovery requisite (sleep) to give creatures a good reason to spend decades asleep in thier lairs.
This is basically giving them minor/major philosophic alchemy for the purposes of might recovery.
Reduced Power can reduce casting total for a power, which reduces penetration, potentially to the point where they need to spend might points to cast it at all.