The advantages of disk brakes are, 1, few moving parts. 2, less "fade" with repeated stops(more air, better cooling). 3, Less money to make, fewer parts(more profit for the Company). 4, Easy to wipe water off of brake surface. 5, Simple to turn and clean up for repair.
Stopping distance is a function of contact patch(tire profile) and friction(rubber compound) If you want to improve stopping distance, use a soft tire and make it wider. As long as the brakes can stop the tires you have enough.
