22 Day Trip China

A friend and I are planning to stay in china for 05.09.26 - 26.09.26 - 22 Days / 21 Nights and have the following plan right now:

Peking must have: Great Wall, Forbidden City and City, 1 Day for Jetlag
Peking nice to have: Red Beach in Panjin Shi
4 - 5 Nights
- Train

Pingyao: old town
1 Night
- Train

Xi’An must have: terracotta army, Hua Shan
Xi’An nice to have: Daytrip to Luoyang
3 Nights
- Train

Chengdu must have: giant panda research, dujiangyan irrigation system (bridges and more)
Chengdu nice to have: Daytrip Giant Buddha Leshan, national park - is it possible to see wild red Panda nearby?
3-4 Nights
- Train

Chongqing must have: City (Liziba filling station + Hongya Cave Dawan Tea at night), Drown show at 19.09.26
Chongqing nice to have: Dazu Rock Carvings
2 - 3 Nights
- Train

Zhangjiajie must have: Zhangjiajie National Forest Park, Tianmen Mountain
Zhangjiajie nice to have: Wangxian Valley Town / Phoenix Ancient City, 72 wonder tower at night, Sky Ladder Zhangjiajie
3 Nights
- Flight

Shanghai must have: city (library, ...), Daytrip to Zhujiajiao, Shanghai Wild Animal Park to see and feed red Panda
3 Nights

Do we need to care about China’s National Day - Golden Week, is there anything more in September to watch out for?

Please add must haves or nice additions to our plan we havent found out yet, or tell us where you might see problems. Thanks a lot in advance!