we will be arriving Shanghai Hongqiao airport on 12/9 and plan to travel to Suzhou for 2 days on the same day. I would like to know whether this is possible by D train from Hongqiao railway station which is located in the same building as the airport, am I correct?

Then from Suzhou to Hangzhou, then back to Shanghai

Is it possible to buy the tickets on the same day or we have to book in advance. I can't seem to find a site for proper full train schedules for Suzhou & Hangzhou. Could you please advise where we can book ticket in advance if we have to do so.

we would like to take D train as it's suppose to cut the travel journey down. I am prepare to listen to any other best options available if it'll cut down the travel time

By the way, is 2 days in Suzhou - visit Zhouzhuang,Ding Hui Temple, Cold mountain Temple, Huqiu Tower, b/w the following choices of gardens: Lingering Garden, Humble Adm's Garden & Lion Forrest Garden, which is the best to visit since we only have 2 days? and 2 days in Hangzhou enough?

Is Longjing Tea Fields worth a visit?

Many thanks!