Hi - I have never been to Shanghai but I simply copy pasted your title above in to google and found lots of positive looking stuff! I think you will have a ball!!
If you have a bicycle why not take it? A mate of mine went to Japan for a holiday of some weeks and yep family and all the roadie went along - fun times were had!
Yes, I spent nearly a year there and cycled nearly everywhere. It was a great way to get around. Bikes outnumbered cars by far. Unfortunately that was nearly 25 years ago so not very useful for you as I suspect that cars now outnumber bikes. Interesting side note is that bikes had to be registered and had a little registration plate. Interesting to see if they still have bike registration there.