Agree with Paul re Novotel in Reims (we were on the same trip). It has good access to the motorway network and you know exactly what to expect. Check out the various ULEZ requirements for Reims, Stuttgart and Salzburg - you will end up with so many stickers on your windscreen that you will have difficulty seeing out. 300 miles per day in a Morgan will be tiring and won't really allow any time for anything other than driving. Check out the Via Michelin journey times and add at least a couple of hours for traffic etc.The autobahns near to and around Stuttgart and Munich can be very busy.