I have landed at Zurich many times, but always in the winter. I don't think I have ever spent more than 5 minutes to get my passport stamped. I have always been at the luggage carousel waiting for my bags to show up on the belt.
Leaving on a Saturday in winter is a different matter. That is skier turnover day and it is a complete zoo. Despite the reputation of Swiss efficiency, chaos is the order of the day. Nonetheless, in the worst possible circumstances, 3 hours has been sufficient to make a flight. You will have secondary security at the gate, and some lucky people will get a special dose of security. It happened to me once, and the Swiss security guy more or less winked at me. "It keeps your government happy." Only people who arrive early at the boarding area get this treatment, as the Swiss do believe that airplanes, like trains are supposed to depart on time. Last minute stragglers coming in on connecting flights just get waved on board.
I did notice a big wheelchair coral in the check in lobby. Skiers usually arrive in one piece, but sometime depart a little damaged.
PS, I have always used Swiss, which has its own check in lobby. I don't how things fare at the other terminal. All the overseas flights arrive and depart from the same remote concourse which is reached by an underground shuttle train. Complete with yodeling and mooing cows on the PA system.