Hi,
For museums, Basel is a good place. The van Gogh exhibition was on till 27-Sep. And from 24-Oct onwards for two weeks, there's the HerbstMesse or Autumn fair, supposed to be good fun.
I would also recommend Luzern, a very beautiful city. Plus there are lots of hikes around that area e.g. hike to Pilatus and back (you save on cable car charges

) or Rigi.
Happy Daytripping,
Nikky