Hi,

We've just travelled a similar route, you may find the stopovers we mentioned on our blog useful clubmotorhome.co.uk/members-area/blog - we only used Aires enroute.

On a previous trip we used a good, roughly halfway stopover, at Bourges. You can see the details here

These would be using a route roughly straight down the middle of France, you may want to consider Eastern France depending on how long you want to spend getting south as the Alps are pretty impressive and manageable at that time of year.

Hope this helps but if you need more help when you have decided on your actual route please ask.