Rhone Valley & Alps

We are hopeing to do a tour of parts of the Rhone Valley and the Alps. Ideally we would like to go when the spring flowers are at their best and the weather fairly decent. Has anyone done this tour. We are trying to decide the best route to take either Le Havre or Calais, we live on the Isle of Wight so either would be okay. We don't really want to go near Paris, can anyone recommend a nice scenic route and possibly an overnight or if scenic a couple of nights stopover on the way. Any advice would be great.