Aiz-en-Provence - lovely.
The palace in Spit is the Diocletian ? I think - you can can't miss it.
In Venice - I would just hop on Vaperetto No 1 and stay there all day
- that is the Grand Canal route.
In Pisa the Leaning Tower is situated in the Field of Miracles; if you get the chance visit the Bapistry. Collectively the Field of Miracles puts the Taj Mahal in the shade IMHO.