How high is too high

I following are basically true about skyscrapers: • they can reach a height where they are impractical and dysfunctional • engineering skills today can take them a lot higher than the current world's tallest But what about aestetics? If you disregard how high you can go (engineering) and how high you should go, and consider only how skycrapers look and how they relate to their skylines: what would be the maximum number of feet you think a building should go while still be an attractive structure and fitting in to its surroundings? (I realize this thread can come up with crazy, off the wall numbers, but I am seriously asking here what you folks think)>