This is a "just thought of it, had to throw it out there" kind of post, so don't expect anything concrete
One of the things that has frustrated me a bit with the way magic is handled in SBG is the limited casting ability of anything short of wizards. This doesn't mean I think magic should be flying around every turn...it should still be hard to do, but it would be nice if it wasn't so limited. A shaman casting channeled Fury has a pretty good chance of fluffing the whole thing, leaving them effectively useless for the rest of the game.
I've been playing a lot of the new Star Wars Edge of the Empire RPG lately, and it has what I consider the perfect Force mechanic. I think it would translate quite well to SBG. The Force mechanic gets rid of point-counting and resolves down to a simple dice pool. If you're just starting out, you get one die to work with, which means more often than not, tapping into the Force isn't going to get you much, if anything. As you grow in the Force you get more dice, and your chances of success are more assured. It's easy to see a potential problem here: by the time you get to 3 or 4 Force dice, you're pretty much in the "guaranteed to work" zone. But basic Force powers aren't that potent...you need to commit dice from your pool to maintain effects, do more than one thing, extend range or power, etc, which keeps the effective pool lower even while letting advanced users do amazing things, yet retaining a reasonable chance of failure.
So what if...
What if every magic user had a magic pool they could roll each time they wanted to cast a spell? A shaman or stormcaller might only have one die, nazgul and Elrond-types would have 2, wizards would have 3 (2, +1 from their staff). Spells themselves would be more difficult to cast, so those numbers would have to go up, but I imagine increasing the difficulty of everything by 1 would be good for a start. Attempting a channelled spell would require the caster to commit a die from his pool. The profile would still have their MWF, so Might could be used to alter the highest die in a roll, while Will could be used to add a die to the pool. In fact, spending Will would be the only way for a shaman to get channelled Fury...
I know the idea and details need some tweaking, but...any thoughts on the basic concept?