You're describing years after the shark episode. (Except for the hair. That happened pretty much after the first or second season.) When Fonzie jumped the shark they hadn't even had the Mork episode yet. And they had only just spun off Laverne and Shirley.
Around the time before the shark the clothing and sets had long been changed. The sets changed by the 3rd season and the clothing later that season. By the 4th and 5th you can tell wardrobe was phoning it in..