I would spend another day in Rome rather than in Florence. We read Rick Steves' description in Mona Winks while we toured the Forum and it brought it to life for us. I would add a rest day somewhere. We stopped for a night in Varenna in the Italian Lakes on our way from Venice to Germany (we were travelling by train). My teens (at the time) really liked Venice. In Bavaria, we were able to stay at youth hostels because our kids were with us. We enjoyed Rothenburg Ob Der Tauber and its great hostel.

Frances Toronto, Canada