We use the same route as Val A, although we have, in the past, gone east as far as Troyes and then cut across country (Nevers, Moulin) to the A75. We love the scenery on the A75, as well as the fact that it is toll-free!
Usually, we see where we are at around 3.30-4 pm and then decide where to stop using the excellent Caravan Europe guide. Much depends on what time we have crossed over from the UK, but it's surprising how long it takes to get as far as Chartres. For those not used to travelling in France it can be easy to underestimate how far you will get - distances are much greater than they look on a map. We have stopped at Chartres a number of times and also at Issoire. Sometimes we have taken 2 days to get to the south, stopping again at places like Limoges. Sites vary and we have been in some tiny and pretty remote ones! The fun is in the unknown. Most sites are fine for an overnight stop, but we do like (if possible) to be within walking distance of somewhere we can eat, as it saves a lot of hassle when on the move.
Jo