I would recommend Portuguese from Lisbon, the central route. I walked last year in late Oct, weather was very pleasant, dry and sunny, there are albergues between Lisbon and Porto now, and excellent infrastructure from Porto onwards. Easy walking, no mountains to cross, could be done in runers, although some cobblestones. Beautiful nature, great food, the route is popular but not that busy at that time of the year. Lisbon to Porto usually takes 13 days, Porto to Santiago another 10. Could be faster depending on your level of fitness. You could start from Santarem/Tomar/Coimbra if you don;t feel like walking all the way or if pressed for time. After Coimbra the distances between towns are smaller, before Coimbra is almost 30km every day. Loved Camino in Portugal, miss it badly.