Actually, I had found a bathtub before: near Shaoguan in a hot spring hotel. Made from wood, you had to line it with a special-made plastic 'bag' to use it.
The good memories about Shanghai are largely related to my girlfriend. Only because of her (she had friends there) I stayed there more than once. The city is too sterile for me (though still far better than Beijing), although back in 2008/09 you didn't have to walk far to get into areas which looked like any other bigger Chinese city. Except for transits I haven't been there since 2009. But thanks for the info about the TV tower.
I prefer smaller cities where you can still find some street life, particularly food vendors.
But, well, emperor Xi made sure that I won't enjoy Chinese street food anymore.