First Europe Family Trip planning - 13-14 days Switzerland/_____ / Italy

We are planning our first Europe trip as a family from India we are traveling with our 17 year old son and 16 year old daughter and would love some advice from experienced travelers.
Our trip will likely be around 13-14 days in late June to early July . We already received our Schengen visa from Switzerland, so Switzerland will definitely be one of the main countries on the trip spending the maximum days.
We definitely want to visit Italy as well, but we are still confused about which other country would fit best for a relaxed first-time Europe trip. Right now we are considering combinations including:
Switzerland
Italy
OR France
OR Germany
OR Spain
OR AUSTRIA
We only want to do around 3 countries maximum because we do not want the trip to become too rushed or exhausting, especially with family. We prefer a less chaotic. and more comfortable trip instead of constantly changing hotels and covering too many places so we want to make base in cities probably thinking two cities in Switzerland and Italy and 1 city in 3rd country .
Our travel style is more about:
Scenic views, mountains, lakes, and beautiful cities
Good food, cafés, shopping, and relaxed exploring
Comfortable travel and fewer hotel changes
A balanced itinerary instead of rushing through Europe
Some questions:
Which 3-country combination would you recommend for first-timers?
Is Switzerland + Italy + France the best route?
Would Germany or Spain fit better instead of France?
How many days would you suggest per country?
Which cities would you personally recommend for a relaxed family itinerary in June?
Would really appreciate suggestions, sample itineraries, or advice from people who have done a similar trip