I suggest you to visit Tongli for watervillages.

And also you can share 2days for Hangzhou( west lake / longjin tea plantation etc). So 4days schedule as below:

1day in Shanghai

1day in Tongli

2days in Hangzhou

or you can stay overnight in Tongli and share 1day for hangzhou.

Enjoy!

i recommend Xidang among the 3 you mentioned.

since you've seen so many gardens, i think Hangzhou will be a good choice for you.

We will be staying 3 nights in Hangzhou after Shanghai.

Hi as this is probably yr only 1 trip to Shanghai ,i would strongly recommend u to so Suzhou,Xitang,Hangzhou n of cos Shanghai.Suzhou is very much different from Japan n u will rest assured u would not be underwelmed.4 days is actually in fact a very short time n i doubt u could acually do these 4 cities in 4 days.China cities by n large has much to offer compared to those in Japan n their sizes u much bigger too.U probably may need at least 2 days for Shanghai alone.No point in doin 2 watertowns so either Tongli or Xitang will do for the watercities.

I would probably elect to spend the 3 remaining days in Shanghai though. Don't forget to stay overnight in Tongli!

Actually the gardens in Suzhou are OK. Not as good as places in Japan, but nonetheless worth visiting.I don't think you will be underwhelmed but neither will you be struck in awe.

In Japan I could fully understand/feel the concept of zen in a garden but that feel is somehow not quite replicated in SuZhou.