In need of route help! France, Italy, Switzerland

Something's gotta give. Don't see how it can be done and actually stay long enough to enjoy any of these spots.

June 2, 3 1/2 hours to Annecy direct TGV
June 3, enjoy Annecy
June 4, 9 hours train/bus to Portofino
June 5, enjoy Portofino
June 6, 3 1/2 hours train to Florence
June 7, enjoy Florence
June 8, 2 1/2 hours to Venice
June 9, enjoy Venice
June 10, ?? You need to be in London the next day on the 11th for flight home on the 12th. Hardly enough time to do anything but wave to the Berner Oberland on the way through.
Cut one stop, maybe 2. I'd say at the very least, cut Annecy. Fly Paris-Genoa and you might have enough time to hit Gimmewald before flying to London on the 11th from Zurich. Either Florence or Venice deserve an extra day.

Let's see: 6 places in 3 countries in 9 days (nights). Is it physically possible? Yes. Is it recommended or advised? No

I agree with Sam, skip Annecy and fly from Paris to somewhere in Italy and work your way through Switzerland and fly from Zurich to London. Maybe skip Portofino also. I'm sure you chose these two (Annecy & Portofino) because of their beauty and they are wonderful places to visit, but they are not particularly easy to get to and from in the amount of time you have.

Your planned routing is good, but I think you are coming up against the reality of time and distance versus what you really want to see. Cut out two stops, as suggested, any two, depending on your priorities.

You will have an on-the-go schedule, but it is more than doable.

June 2, 9:50 train, 3 1/2 hours Paris to Annecy direct TGV - Arrive 13:30, afternoon and evening in Annecy. Sleep in Annecy

June 3, morning in Annecy; 14:39 train, 5 hours to Interlaken, arrive 19:51, 20-minute train from Interlaken to Lauterbrunnen. Sleep in Lauterbrunnen

June 4, Enjoy Bernese Oberland, Sleep in Lauterbrunnen

June 5, morning in Bernese Oberland; 13:29 train, 6 hours Interlaken to Venice, arrive 19:28, Evening in Venice. Sleep in Venice

June 6, Enjoy Venice, Sleep in Venice

June 7, Morning and Lunch in Venice. 15:37 (or 16:37) train, 2 hours to Florence, arrive 17:30 (or 18:30), Evening in Florence. Sleep in Florence

June 8, Enjoy Florence, Sleep in Florence

June 9, Morning and Afternoon in Florence. 16:34 train, 3 hours to Rapallo, arrive 19:31 (possible quick hour or so stop in Pisa if you leave earlier or arrive late), evening in Santa Margherita Ligure. Sleep in Santa Margherita Ligure.

June 10, 10-minute bus ride to Portofino. (also not far from Cinque Terre). Sleep in Santa Margherita Ligure.

June 11, 30-minute train from Rapallo to Genoa. 10-minute bus ride to Genoa Airport. Afternoon or Evening flight from Genoa to London.

Many would feel that this schedule is way to aggressive. It is aggressive, but very doable and allows you to see everything on your list. Happy travels!

It will be a 'taste of' all those countries. It could be a lot of fun, or it could be grueling. It looks like about 20 hours on the train, plus the time getting to train station from hotel and on to new hotel. But, if those are the places you want to see and don't mind an aggressive travel plan, then go for it. You will have time to rest on the train:) I have certainly done trips like this, however I usually have a car so my travel can be more flexible. I also don't make reservations in a lot of cases so there is the freedom to change my mind if I find a place I am just not willing to leave. Either way... it is your trip... so do it with no regrets!

Thank you all so much for your time and for the thoughtful replies! They are so appreciated and very helpful!