Gstom, they're excellent prices for what is only a little more travelling.
Defo with the bike trip going to book that route, when I go with the Doris in July in the car, as she's not good on water, we'll book the overnight to Caen as we always do. However, including a sea view berth both ways we're looking at over £600
Hmm, we used that run twice a year when we first had out house here in the Pyrenees but lived in Brighton. Trouble with it being that you have to go through Rouen where we almost always got lost despite it being around midnight and so no traffic. So after a few years we found that the Portsmouth to Caen run infinitely better...
Crossing the Pyrenees towards Zaragoza via Portalet is pants as the run up from the French side is long and congested and from Sabinanigo it's motorways only until well beyond Zaragoza. Canfranc and Jaca is a bit better but still motorways from Huesca. Think about the Vall d'Aran route. The road to the frontier from Montrejeau is greatly improved with the bottlenecks bypassed, especially St. Beat, and of course you're in Spain - cheaper fuel, drinks, better food and friendlier people! - on the north side of the Pyrenees.
After that you have two routes to Lleida and from there a sublime run to Cuenca via Teruel: Caspe, Alcaniz, Escucha, Alfambra....