As you may see alot on the forums, possibly the best advice you will get is to travel and stay in the areas as much as possible beforehand.
This way you will experience first hand if the area your looking at is best for you.
On a number of forums I see countless people blow the trumpet for their own area, but everyone is individual and what suits one person may not be right for another. I love the area where I live, and am always happy to sing its praises, but it might not suit everyone.
This forum certainly is an excellent source of information, with the guides that have been posted, along with a good spread of people posting throughout Spain itself.
Good luck with your research. If you have specific questions about anything or anywhere, you’ve certainly come to the right place.