4 night 5 day swiss itinerary review/ advice 🙏🏻

Me and my family were planning a 5 day trip to Switzerland in first week of April. Me, wife and 2 year old.

Our current basic itinerary is:

Day 1 land in zurich (reaching 7 am), travel to lucerne. Explore lucerne.

Day 2 lucerne, mt pilatus

Day 3 lucerne to interlaken scenic train. Stay in interlaken. Explore luternbrennen and come back to interlaken.

Day 4 explore Grindelwald or go to jungfro (top of Europe). Come back to interlaken stay.

Day 5 . Walk around and explore interlaken till afternoon (read there is fornicular to a sight seeing spot). Train from interlaken to Zurich airport. Flight back home in evening 9 pm.

So here are my concerns and questions. Should I base day 3, 4 and 5 in interlaken or should I base those days in Grindelwald? A lot of websites say interlaken is not so great.

Option 1: base interlaken. How should I spend day 3, 4 and 5.

Option 2: base Grindelwald. How should I spend days 3, 4 and 5. And on 5th day how do I go back to Zurich airport from Grindelwald.

We plan to take the full swiss travel pass. It should cover all the trains I believe.

We are looking for a relaxing, sight seeing and calm vacation. Would love to take in all the scenic beauties. Since I have a two year old I would be avoiding all adrenaline sports, hiking etc.

Also, should I visit jungro top of Europe if I am already visitingt pilatus.

I know it's a long post. Any help would be much appreciated. Thanks.