Suggest you go to Shanghai to take the flight. Wuxi is closer to Shanghai. It has bullet train to Shanghai and get there within one hour. Or you can take buses at Wuxi North Bus Station to Shanghai Hengfeng Road or Shanghai Railway Station and South Railway Station. Recommend you catch the buses to the railway stations where you can take airport buses to the airport. It needs 1.5-2 hours to Shanghai and the buses are leaving from Wuxi every 40 minutes or so. It is easy to get one and no need to nbuy ticket in advance.