Our base was Switzerland and we did a ten day driving trip in Italy. Como first day, 2nd day Cinque Terra. 2 days in Rome. One day in Florence. A DAY IN Venice. Trieste one day. And Bolzano a day before driving back to Switzerland thru Innsbruk and Liectenstein.

In Switzerland, A couple of days in Interken, Grinderwald Lauterbrunnen Wengen Schilthorn( James Bond).
A day in Zermatt Matterhorn
A day in Montraux area with a visit to Gruyeres ( cheese and village) about 10 minutes from Gruyeres is Bloc where the best chocolate factory tour is. You could do Bern or Luzern pirates tour gondola/ tram up, cog train down and boat back to Luzern train station.
BTW, served mission in Italy and parents are from Bern Oberland. Interlaken, wengen, Lauterbrunnen.