In Suzhou for two weeks where to visit? Would like to see some beautiful natural areas.

Well, in SZ, the must see is the classic gardens, here are some reputed ones: Hungble Administrator’s Garden, Lingering Garden, Blue Wave Pavilion, Lion Grove Garden.

There are also ancient towns for sightseeing: Tongli Town, Zhouzhuang, Wuzhen.
For night landscape, there are Tiger Hill and Panmen Scenic area, or you can go to nearby Hangzhou for the West Lake.

When will you be in China? It is a peak travel season in Yellow Mountain presently, especailly the days Oct 1-7 and it will be very crowded there. So you are suggested to avoid travling there in the fist days of October. For other time, it should be OK although there will be more visitors than usual. Yes, it is expensive to visit the mountain compared with other scenic site, as 1) it is located a little bit far and the transportation costs more; 2) you may need to stay ovenight there, so accommodation will be extra pay; 3) the entry ticket is pricey than other attraction sites.