I'd recommend walking south, over the Somport.... It's a remarkable experience.
That said, as I observed in an earlier forum post, while I'm glad that I did the CA this past May/June, I would not do it again.... Once was enough.... It's "feel" is very different from the "feel" of the CF, as other walkers will confirm, I'm sure....
The French section was wonderful, and the French so surprizingly hospitable that I've promised to stop bashing France.... Much nicer treatment received than in jaded SJPdeP! The Somport Pass mountain scenery was absolutely stunning, and the historical sites (especially Jaca Cathedral museum, San Juan de la Pena, Leyre Monastery) were memorable....But I found the CA in Spain less and less rewarding the farther I went -- probably because my increasingly vulnerable old back just found the CA too physically tough....
And it was comparatively lonely -- if you enjoy the "social" side of peregrino life, the CA will disappoint.... I was relieved to finally arrive in comfy old Puente la Reina Gares, with its peregrino hoardes marching down the Calle Mayor....
So: If I were to go back, myself, I think that I might walk on through from Oloron to SJPdeP....
In any event - I'd recommend that you fly into Toulouse, and explore it -- one of the most attractive and liveable modern cities I've ever visited, with many Camino associations! -- and then bus/train to Lourdes -- and then spend at least an entire day exploring that strange-but-wonderful place, before you set off into the west....
Fr J