Suggestions - set Betty to find Teruel, Cuenca, Alarcon...if you're headed into Castille proper, then Segovia and Toledo.
If you're trying to follow the sun then head to Cordoba and Granada, Malaga, Torremolinos, etc
If you're trying to follow a more gastronomical path then head up to Galicia- Vigo, Santiago, Bilbao and the Basque Country- you might find more rain however......the views and food might make it worthwhile...and, you can hit the Bordeaux region on your way back home! You could, of course, just as easily hop a ferry to Africa...
The Paradores Nacionales might be running off-season specials that may make staying in a castle more affordable and, although they might not have WiFi, they do specialize in the the regional cuisine of the area.