The only thing you can find online is usually catering to rich western tourists or "expats" and usually boils down to "Which place is the most western/ High GDP and McDonalds!" so I'd rather get an opinion from someone that's been there that isn't a business tourist.
There's a saying in Chinese 上有天堂,下有苏杭 which means 'Heaven is above, on Earth there is Suzhou amd Hangzhou'.
I loved Suzhou. Suzhou is a large city about an hour west of Shanghai (half hour by HSR) in the wealthy province of Jiangsu (think Newcastle relative to Sydney, Geelong to Melbourne). It's an old city full of canals (I mean... all the cities are old) built close to the Great Canal. It's reputed for its old silk culture and style of opera (not as famous as jingju but quite nice). Hangzhou in nearby Zhejiang province is probably a bit too tech-y, influencer-y (it's the headquarters of Alibaba) but is considered one of the most aesthetically pleasing cities in the country alongside Suzhou because of the West Lake and its rolling tea fields. Nanjing (the capital of the Jiangsu province) is very nice too and probably overlooked.
Other cities tend to be those that are within commuting distance from major cities like Zhuhai (close to Shenzhen) for employment but not over urbanised yet.
Wuhan was also pretty damn nice. It's kinda hard to go wrong. I also watch videos of an influencer who lives in Changchun (whose name means 'Eternal Spring') and honestly it looks lovely in the right seasons. It's always subjective though because I've always lived coastal and don't think I'd be able to live inland.
It's sad to see 苏州 (suzhou) characterized by its relationship to 上海 (shanghai), when 上海 is merely a city invented by China within the last 100 years to interface with the capitalist west. 上海's culture draws from the original, ancient cities of 杭州 (hangzhou) and 苏州. If history had played out slightly differently, 普通话 (common speech) would probably be their 吴语 (wu chinese) due to 南京 (nanjing)'s influence.
I did have friends who lived in the suburbs between SZ and SH and commuted daily to SH, so its current economic influence can definitely overshadow the historical relationship between the two cities.