Is Tokyo, Japan a must-visit travel destination?

Japan - Osaka area, Northern Kyushu
Taiwan - Taipei, Tainan, Kaohsiung
Hong Kong
China - Beijing (only visited the Summer Palace)
Europe - Austria, Hungary, Sweden
I have traveled to these places, and now I am deciding whether to visit Taiwan again during the Christmas holidays or go to Japan. If I go to Japan, I am considering Tokyo or Sapporo. I am hesitant about Sapporo because it is expensive and there are concerns about flight cancellations. Is Tokyo worth visiting?