Avid single digit 7 brakes release
 

There's probably a simple answer (but no dumb questions, right?): is there a quick release -- or similar fast fix -- for these brakes, either on the lever or on the brake itself? I need to regularly remove the front wheel to put my bike on a roof rack.

The noodle on the brake can be un-clipped, this is the same for almost all linear pull (v-type) brakes

Nix: Squeeze the brake pads together against the brake tracks with one hand, this will release the tension on the brake cable and you should be able to pull the noodle out of the brake arm with your other hand and release the tension to allow the pads to retract from the wheel.