Hi Daxu,
like your finds too! I agree with yor dating of the first two, the dragon bowl I just don't know for sure, however it is certainly hase some age. Why do you think the cup is Qianlong? The decoration seems to me to be in the "Rose Medaillon" pattern, and if there is no red "CHINA" mark on the bottom, it likely dates to the second half of the 19th century, before 1890, when they started putting that stamp on the bottom of pieces for export to the U.S.
Regards, Mat