So we booked our tickets to Hawaii for December. We'll only be there from Monday to Sunday and I would like to split the time between Waikiki beach and the North Shore. We are young and would like to stay in the more lively area but we can get pretty tired of it so I thought we can stay in North Shore for a few days. We're thinking about 3 days each. Any thoughts on whether thats enough time to do things in each city? We don't care to do everything but we want to snorkel, go to Pearl Harbor, Diamond Head, maybe take some surf lessons. We plan to have a rental car for the time in North Shore.