T-minus 7 Days until I arrive in London

I have exactly 1 week until I arrive in London. I have been making last-minute lists of what to pack, and how to remain secure while I travel throughout Europe. Most of the hostel accommodations have been booked, except for 3 days in France. I haven't decided yet if I want to stay in Paris longer, or just go to Cannes/Nice area and stay for 3-4 days on the French Riviera.

Today I just inquired about kayaking tour of Venice on May 2nd. Hopefully I will hear back from them in the next day or so. Since I only have 3 days in Venice (2.5 really), if I am unable to get the kayak trip reservation, I won't be too upset.

My trip itenerary is as follows:

4 days in England (1 of which is in Bath), 4 in Paris, 3 on the French Riviera (Cannes/Nice), 3 in Venice, 2 in Florence, 1 in Pisa (day trip from Florence), and 4 days in Rome.

I am quite sure that I will be fully exhausted by the end of my trip. :)