Thanks for all the suggestions. To answer a few questions: I do have my flights booked(incoming to Rome) and Madrid(going out). Also, i had to remove Switzerland due to lack of time(painful decison but may be next time). I also changed itinerary: Its Rome-Pisa(stay overnight)-Venice(2 days). I just had to look at Italy map to see my original idea was very bad(Rome-Venice-Pisa) :-)
I will take Thello train from Venice-Paris and spend 3 days in Paris(had to see Versailles) and then booked flight from Paris to Madrid(Train ride was long and we have another 14 hour journey back home). Also, I wanted to maximize my time in Madrid.