Octopus Card or Airport Express Travel Pass?

Hi,
Just like to be clear - I'm travelling with my wife and 14 month old son. We are staying in Ramada Kowloon and will be visiting Temple St. Night Market, Macau, Lamma Island, Mongkok Market and maybe Sai Kung. Can you please let me know if On Loan Octopus Card is better or Airport Express Travel Pass for my entire stay? And why? Thanks a million!!