If you are a history buff, then you may consider adding the Pancha Rathas and Varaha Cave to your itinerary. Nature enthusiasts can plan for a beach visit to Mahabalipuram Beach or Serenity Beach.
If you have more time, explore the Sculpture Museum or shop for souvenirs at the local market. If you have less time, cut short the lunch time and give only 30 minutes each to Arjuna's Penance and Shore Temple, respectively.