Yes, depends on what you want, but I strongly recommend min 1 day in bkk. Check the night life along Sukumvit and visit Nana and Soi Cowboy. There also many great night markets with the visit if you are a food guy.
Use thai or Asian airline.....cheapest and good service. Try to visit Karon Beach in Phuket which is 30 taxi, 500 bht. Water is much cleaner and less crowded.