If its your first trip to Phuket and its your honeymoon, I would suggest splitting your stay between Patong and the JW Marriott.

Patong is convenient for eating, drinking, shopping, arranging tours etc but not quite an ideal place to laze around. You can stay there for a few days when you first arrived and get all your shopping, tours done etc

After you are done with the shopping, tours and nightlife in Patong, you can move on to the JW Marriott at Mai Kao Beach which is a very beautiful resort but located in a rather inconvenient location. A good place to laze around. Note that some tour operators do charge extra for pick-up at the JW Marriott, so it may be a good idea to do all your sightseeing before coming here !

Kata is near the Kata View Point and Phromthep Cape which are worth visiting. I dont know about dive trips but most day trips to Koh Phi Phi and Phang Nga Bay use the harbour/jetty at Rassada Harbour and Ao Po (or jetties nearby) which are not quite near Kata/Karon/Patong . However most tour operators for these trips would pick you up from your hotel, so it doesnt really matter where you stay.