Magisters should probably not be allowed to use Source skills at all. I mean, it's their whole THING.

I also fail to understand the reasoning behind removing the Source Puddles lying around. Those are pre-placed, single points, and often you needed to send a character after them immediately so an enemy wouldn't suck them up. It offered at least some method of getting Source if you didn't want to suck up Source Jars for role-playing reasons.