thanks
On these 3 longer journeys we will have luggage so trying to reduce the pain of changing but also keeping an eye on the cost.
I had spotted on some photos that several panoramic trains had local trains attached however I now realise that is only for part of the route.
I'm not sure how far you have got with hotel bookings, but as I understand it at present, you are now planning two bases, Interlaken (two free days, your 'days 2 and 3') and Chur area (3 free days, your 'days 5,6 and 7') (that's what I would recommend anyway - the fewer bases the better in my view)
To enhance the experience, you still have the alternative to save the 'Glacier Express' route for a day trip without luggage on day 5, 6 or 7. You could switch between the hotel bases by main line SBB trains (larger coaches so somewhat easier to deal with luggage than on the metre gauge stock), e.g. Interlaken - Bern - Zurich - Chur. This route has some advantages
(1) it is quicker than going via the mountains, potentially attractive when switching between hotels
(2) you would see a bit of the 'Mittelland' - the very pleasant undulating central plateau of Switzerland
(3) you would get the very scenic run along the Walensee lake on the Zurich - Chur train, then pass through 'Heidiland'
You could then do the most scenic section of the 'Furka-Oberalp' part of the Glacier Express route, which is Chur - Andermatt (the rest is less scenic since the Furka tunnel was built) on a day trip, even better would be a circular day trip Chur - Andermatt - Göschenen - Wassen spirals - Arth Goldau - Sudostbahn - Pfäffikon SZ - Ziegelbrucke - Chur
To sum up the above, the advantage of giving yourself as many 'free option' days as possible (as opposed to fixing yourself to travelling a 'classic scenic route' on a specific day is the weather. In Switzerland it is always worth giving yourself the chance to avoid poor weather in one area by going in a different direction to that originally planned for the day.
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