I am not originally from Shanghai but as a Chinese domme, Shanghai is my favorite city. A bunch of my subs/slaves like Shanghai the most among all the Chinese cities.
Shanghai has very low crime rate. The risk of being mugged or kidnapped is very rare. I walked many times alone in small street in late night and nothing bad happened.
You can use super developed public transportation systems to get around in Shanghai. Metros, buses, shared bikes are everywhere.
You can enjoy food diversity here as there is a wide range of good international restaurants & bars in Shanghai. It can take you a decade to finish trying out all the food options here.
Cost of living is high here as it is the top expensive city in China. If you wanna reach a pretty comfortable level of life here, you’d better earn 40K~ 50K RMB monthly if housing is not provided by company.
Shanghai has a population of 24~25 Million people so you can encounter tons of crowded corners in Shanghai. Occasional excursion to suburb is good to obtain peace and quiet.