Hello again RLS
What I am going to now suggest is an amended, shortened, version of what I suggested in my reply 4 to your previous thread.
I will be assuming that you will be investing in six-day Swiss Travel Passes.
I think I need to stress that Swiss public transport is extremely good. Way, Way better than in Britain or in any other English-speaking country!
As members of this forum have been stressing in a recent thread started by ‘Swiss Trip’, people in their EIGHTIES often take holidays/vacations in Switzerland, touring the country using the superlative public transport. (Read all the replies in that thread, but particularly the very perceptive reply from Andrew.)
March 6th
If your flight arrives before about 14 00, take the train to Montreux (https://www.myswissalps.com/town/montreux/), and stay overnight in that delightful lakeside town. (Nearby Vevey is just as delightful and probably a bit cheaper.)
If arriving after 14 00, stay overnight in Geneva (https://www.myswissalps.com/town/geneva/).
March 7th
If staying in Geneva, catch the 08 05 IR90 train from Geneva to Montreux, arrive Montreux 09 09.
Reserve seats on the 09 33 ‘Golden Pass Express’. Travel through to Interlaken Ost, arriving there at 12 48.
Take a break. Park your luggage in a left luggage locker. (All more important Swiss stations have lockers.) Have lunch and take a stroll.
Catch the 15 06 or 16 06 train to Luzern (the German name for Lucerne). Stay two nights in Luzern (https://www.myswissalps.com/town/lucerne/).
March 8th
Either just stroll around the city, or (my recommended option) take the 10:2 boat bound for Fluelen and just stay on this boat until it gets back to Luzern at 15 47. Have lunch on board the boat (https://www.myswissalps.com/activity/boat-lake-lucerne/). You do not have to disembark at Fluelen.
March 9th
Travel to Chur as detailed in my earlier reply 4.
However, break your journey at Andermatt. Park your luggage in a locker; have lunch; go for a stroll.
Then catch the regional train which leaves Andermatt for Disentis at 28 minutes past each hour. Make the very easy cross-platform interchange at Disentis. The journey to Chur will take in total two hours and 34 minutes. The scenery is extremely good!
Stay two nights in Chur.
March 10th
You could just stroll around Chur; perhaps take the short but extremely exciting bus ride to the small village of Tschiertschen. (Buses run hourly!)
But I would recommend you take the IR38 train to St Moritz (via Filisur). Trains run hourly. The spectacular journey takes two hours.
Have lunch in St Moritz, go for a stroll by the lake.
Then catch the RE7 train which runs hourly to Landquart via Klosters. This train takes just under two hours. It is a very short train ride from Landquart to Chur.
March 11th
In the new timetable commencing in December 2025 Inter-City trains on the Chur-Zurich-Basel route will be running every 30 minutes 365-days-a-year!
On some trips, a change at Zurich is needed. I suggest you (anyway) break your journey at Zurich and park your luggage in a locker. Have lunch … go for a stroll….
Bahnhofstrasse, about one mile long (1.6 kilometres) leads from the Hauptbahnhof to the lake past some very up market shops and (at Paradeplatz) close to the centre of Swiss Banking. If you do not want to Walk, catch a number 11 tram/streetcar.
Conclusion
All this is possible because Switzerland has the best public transport system in the world. The Swiss Travel Pass gives you the freedom of that system.
Very best wishes
Roger