The 7-8 click standard is meant as a way to measure how tight to set the parking brake. It should click a certain number of times when a set amount of force is applied to the ebrake handle. This set amount of force may or may not be enough to hold the car. It is ok to pull the brake a little harder if you need to keep the car from rolling (ie a hilly parking space with wet brakes).
The e-brake is supposed to be self adjusting even after a brake pad/ shoe change. For the rear discs.. They will adjust to normal after the regular brake pedal is pressed a couple of times. For brake drums, a few pulls on the e-brake handle (racheting) will adjust the parking brake to normal height.