Aesthetics of simplicity?

I sometimes have to wonder about just how traditional simple aesthetics is in Japan.  For all of the simple aesthetics found in old temples, Japan sure seems to like large extravagant buildings.  A visit to Odaiba or Shinjuku quickly yields large buildings of complicated, if not futuristic appearing designs.  Even areas with a traditional flare often are very extravagant in their own right by providing a sensory overload of symblism.  A desire for the large and untouchable also goes back hundreds of years.  Nagoya and Osaka castle are anything, but quaint structures.  Powerful temples in the past were also made very large, requiring full tree trunks from overseas to sometimes be importeted to make the temple larger than it otherwise would be able to be.  Size and power seems to have existed for a long time, so perhaps some simplicitiy was due to economic reasons and then romanticized later rather than pure aesthetic value.