The central waterfront is walkable, and taxis are easy for short hops to the pier, restaurants, and Ecocentro. Buses cover parts of town but are not convenient for the wildlife sites.
For El Doradillo, Punta Loma, Peninsula Valdes, and Punta Tombo, a rental car or organised tour saves a lot of frustration. Distances are bigger than they look, roads can be gravel, and wind changes the feel of even a short drive.