I am currently planning a family trip to Italy and Switzerland. We will be leaving Venice on August 21st and staying in Switzerland for 4 nights. We fly out of Zurich on August 25th. We will be staying in Zurich on August 24th, but wasn't planning on seeing much in Zurich since we want to spend most of our time in the Alps. I'm predicting taking a train later in the day to Zurich to maximize our time in the Berner Oberland area.
Question: where should I stay for 3 nights in Switzerland if I'm traveling from Venice?
Places I want to see: Bern, Grindelwald and Jungfraujoch.
What would be the best home base to visit those three places? Keep in mind, I'm traveling from Venice and I do expect at least 6 hours of travel to arrive in Switzerland. I would love your advice!