Across the China Sea from Taiwan is the island city of Xiamen (small by Chinese standards at a mere 2 million), a destination worth setting your sights on for its beach lifestyle and the bohemian novelty of the small sister island, Gulangyu. Although it garners less attention than the tourist-trafficked city of Sanya on Hainan, Xiamen is one of the best places in China for palm tree-guided strolls and kitesurfing, although there are reports that some beaches are not entirely swimmable due to industrial pollutants. Kitesurfers, both experienced and not, should try Haiyuntai Beach, where you'll find a kitesurfing school and prime conditions.
The jewel of the area, though, is Gulangyu Island, a pedestrian only swath of land that is popular for beaches, gardens, and scenic locales, as well as the curios and pieces of island art that can be procured along Longtou Road. Although not the cheapest destination (you'll pay to enter any "garden" with a view and the locals live solely off of the tourists), you'll enjoy the period European architecture that remains from colonial times and the carefree quiet of a place without gas-guzzlers or pretentious attitudes.
Make Xiamen and Gulyangu a part of your trip, as they'll make for an excellent leg on a journey through China.