Iberian Peninsula - 8ish weeks - suggestions?

Spain and Portugal, have you been to either or both?
Portugal: I would use both Lisbon and Porto as your two bases to explore Portugal. With only one of these bases, you will not comfortably be able to visit many of Portugal’s major sites.
Spain is a very large country so I recommend these to fit with your desire to visit both the Basque region, Andalusia and Spain’s two largest cities.
Basque region: San Sebastián or Hondarribia( 20 min. apart.) We stayed in Hondarribia as we felt it would be easier getting in and out with our rental car. We had a car the whole trip, except for Lisbon, Porto, Madrid, Barcelona.
. If you rent a car be aware that you will want to pick it up and drop it off in the same country to avoid a large drop fee. We were quoted a 1000€ drop fee. We dropped the first car off in Porto and had a driver take us across the border to Galicia in Spain where we picked up a Spanish rental car. We returned the car in Barcelona.
Andalusia: Sevilla
With eight weeks, why only Madrid or Barcelona? They are very different from each other and both deserve time and should be visited. . Madrid is culturally Spanish, while Barcelona has strong Catalan influences rather than Spanish. I prefer Madrid myself.
The biggest help we found when traveling to Spain the first time was MaribelsGuides.com. They had information that we used every single day of a six week long trip. You can also send her questions, a very helpful woman who knows this region of the world well.

I just did 9 weeks in Spain/Portugal this summer, but I did the "shark" version, because that's how I prefer to travel. As the previous poster mentioned 3-4 bases is a little difficult, especially for Spain, since it's such a large country. However, I'll comment on your ideas so far. I've never travelled to the far north of Spain, so I can't comment on San Sebastian. In Portugal, I think Lisbon is the best home base, primarily because out of the three times I've travelled to Portugal, it's the city I love coming back to the most. On the trip this summer, I visited basically everything north of Lisbon all the way to the border with Spain. I didn't visit the Algarve. If you want something between Lisbon and Porto perhaps Coimbra is the best bet. I personally wouldn't want to do a long stay there because I don't think it has nearly as much to offer as the two biggest cities.

On the southern coast of Spain I would recommend Malaga. The best town in Andalucia to stay is Seville, but it's not on the coast. You can get to Granada and Cordoba as well as Seville from Malaga, but it's a bit of a journey and probably best to stay at least a couple nights.

Madrid vs. Barcelona is difficult. I much prefer Barcelona as a city, but Madrid is more central and easy to get to Segovia, Toledo and even Avila and Salamanca from there. Barcelona also has the coast if that's your preference. Both have tons to do and easy car rentals.

No, Rick has never written about Mallorca. I spent a week there this summer and it was one of the most gorgeous places I've ever seen in 20+ years of travelling. I would highly recommend it. I rented a car to drive around the island for a few days and then finished in Palma. Both experiences were amazing. Yes, Mallorca is touristy, but the driving from place to place was the highlight for me, especially the western coast where the mountains are.

Great feedback. Thanks. Your advice and feedback -- a la rental cars, Mallorca, and alternative destinations -- give me a better focus...

FYI one of my best friends and his wife returned this weekend from San Sebastien. He said it's magical -- and he's been around.

Cheers! and "keep on travelin' "