You're welcome. This forum is a great place to get advice and be helpful. I've had lots of useful feedback here.
Up to Basel from Turin, according to my Cook's Timetable, is a day's travel. Are you planning a whole month because, if you are you'll get lots more in to your trip. Those destinations you've mentioned will give you plenty of variety and they will join up nicely with night trains.
I'm taking a 10 days in 22 pass, starting at the beginning of July, like I did last year as I find that moving on every two or three days is perfect. As I don't get a discount, because I'm (well!) over 26, the one month pass is quite expensive and not really necessary.
The plan for this year is to take 4 or 5 days in Barcelona before my pass begins and then have another 3-4-5 days somewhere warm and sunny at the end of my pass which will make a full month's holiday.
After Barcelona I have thought about going along to Marseille or Nice and then down to southern Italy to take the ferry - very cheap for Interrailers - over to Athens-Thesaloniki-Belgrade-Budapest-Munich and ending in Bordeaux to fly back to Luton.
That will work out quite nicely though I have thought about going back to the Swiss Alps, before heading to Greece, as it is just so amazing there and it's the kind of place that you can keep returning to.
When are you planning to go? Perhaps we'll bump into each other!
Oooh, that's nice, I wanted to see the Alps/Switzerland as well. I've been looking at some maps (dangerous) and I thought perhaps Turin-Milan-Basel/somewhere that side of Switzerland-Paris-Munich-Cologne-Berlin-Prague. Does it sound feasible?
Thank you so much for your help! Where are you planning on going this time round then?