DFRPG accomplishes all three of those handily.
a: by using Refresh as both character feature currency and narrative control currency, casters and noncasters get roughly equal power levels if they have the same starting Refresh.
b: Spellcasting *always* inflicts mental stress, which can take you out of the conflict if it builds too high. The more powerful the spell, the more stressful it is. If you channel up more power than you can control, you have to choose to let it hurt you or release it into the environment under the GM's control.