No, we just love the place. It took me a while to get Mrs Muz to agree to going there, she was convinced the whole place was like Benidorm
For the wine & food stopovers, see
http://www.espana-discovery.es/en
For wild-camping suggestions, see
http://www.furgovw.org/mapa_furgoperfecto/
There was definitely no Bongo-parking in Marseille, plenty of parking but all underground height-barrier places, so the TGV from Avignon seemed a civilised alternative. The train into Barcelona we've done before on other tours, and also into Valencia, Madrid and Lisbon, much better than cooking your Bongo in traffic.
Andorra was a disappointment I'd have to say, but worth going to tick it off the list. Montserrat and Barcelona definitely worth making the effort for. You can get a train from Barcelona to
Castellbell i el Vilar - Monistrol de Montserrat on the R5 line, from there there's a rack & pinion train up to the Monastery. We took the cablecar instead as there's wild-camping in the cablecar carpark.
You need to plan. Do some research, particularly timetables of places you want to go and trains if you're going to use them, and potential places of interest along the way. Be realistic (I'm a fine one to be preaching that
) on what you can do in a day, and the holiday will be so much more of an achievement.
I'd also challenge the view on your child being ok driving through France, they'll probably be asleep most of the way. You can get any number of ferries or the tunnel to France and then hit Andorra, then from Barcelona drift west towards Cantabria
When possible I like to use different routes, different operators too if possible, to add to the overall experience. You're stuck with Britanny Ferries for Santander but for France you can use Condor Ferries from Weymouth or Poole to Saint Malo, DFDS from Dover to Dunkerque, EuroTunnel from Folkestone to Calais (the tunnel is an experience if you haven't used it and don't have LPG power), LD Lines from Newhaven to Dieppe or P&O from Dover to Calais. From North Wales any of those would do and you can tie in places en route in Wales, England & France to suit. Weigh up the cost of your Santander crossing (including cabin) against the fuel and much cheaper crossing from France. I'd recommend doing Santander one-way only and drive through France for the other leg
The LD Lines Gijón to Poole service is now abandoned.
One last thought, being able to speak a bit of Spanish is a big help. In Benidorm they all speak English but inland they don't. Sure, in Barcelona they'd rather you spoke Catalan but a bit of Spanish will get you a long way
Any questions, ask away