Wonderful trip! I strongly recommend several of the Optional Experiences to make the most of your time, including the sunset boat trip in Paris (you see the Eiffel Tower aglow!), walking tour of Hidden Venice, and walking tour of the Colosseum in Rome.
Be prepared to walk a lot (I hit 10-14k steps most days!) Be prepared for early mornings.
We had a great experience on our trip in London. From there we did day trip excursions to various locations in England. These tours were are a bit rushed but overall very pleased. The only thing that was tricky was the tour does not bring us back to the original starting point that was walkable back to our hotel. It would be helpful to plan for this and the extra cost for the cab back to our hotel.
Also, one of the day tours was cancelled but they let us know right away and offered to reschedule. The Claremont hotel in London was fantastic.Location, concierge, breakfast bar and room were an A+ experience and would highly recommend. Michael was very available to help plan the trip and respond to my questions. I would use this tour company again in the future.