Swiss rail pass for scenic trains -- First class vs second class

On the trips you mention, there are two types of train, the official express trains and the regional or local trains. The big difference between the two is the occupancy - the express trains are usually pretty crowed, which means for the most part that you will be restricted to your assigned seat and will not be able to move around to get the best views etc... so for me it is debatable as to whether a first class ticket is worth it.

On the regional trains there is usually plenty of room to move around, open up the windows for photos etc... So I usually go for a second class ticket on the regional trains. Also, remember that you can always upgrade a second class ticket to a first class one of a section of the journey should wish to.

Another little trick you can sometimes do is to check out the dining car, some of them have larger windows and for the price of a coffee or two, you can sit there for most of the trip... Although if they are very busy you may get a hint to move on.

On the Golden Pass route back in November, I went back and forth on seat reservations until the Rail Europe adviser said hey don't worry, at that time of year there are plenty of seats.

And they were right. Also realize that from Geneva you will take a regular train to Montreux and transfer to the Golden Pass train, which is a private line. You'll change trains halfway to Interlaken as well, but it's only 5 steps across a small platform.

I always take the normal trains and sit in second class. The views are the same, the air is fresher, the fellow travelers are often locals, and I keep my money.

Windows open so the pictures are far better than shooting through curved glass with reflections and distortions.