Other mistake: The guys lasso the bear. Then Peter impossibly lassos the bear's legs. There's no way for the lasso to go around the bear's leg with his feet on the ground. And the lasso couldn't have gone over the body down to the legs since the other ropes would have gotten in the way.
Other mistake: In season 4 episode 7, 'Brian the Bachelor'. Cleveland is sitting in a chair in a waiting room and is getting really nervous. Peter tries to help him by tying him to a chair and when that doesn't work, he takes off all of their clothes. Peter ties Cleveland's hands to the arms of the chair and then takes Cleveland's clothes off. He couldn't have taken the shirt off while Cleveland's hands were tied to something without untying him or ripping the shirt, which he didn't do.
Other mistake: After the hurricane passes, Peter acts like he's been impaled by a wooden plank. He pulls it out as if it was attached to his right side. However, the way the metal on the clasp was bent, the only way the wooden plank could've been positioned that way is if the metal was over his shoulder.