First I wish you every success. Clearly to ‘taste and try’ is the only way but in my recent search for my final abode I have gathered a few thoughts:
The north (as in Gilicia, Asturias, Cantabrica) is beautiful but a humid climate with rainfall I think is the negative as you get older.
There are options in land if the coast is not your dream. Clearly prices are lower. If you chose Andalucia then beware in summer the tempretures can be extreme but possibly with 10 years in Mexico that is not such a problem.
The coast of Catalunya has some marvellous locations but they are beyond my budget.
As for the news and the outside world you can certainly live in some laid back ‘manana’ villages but equally the bars are full of lively discussion including soccer, the economy, politics and the world (I believe in that order). That said as a retired foreigner you can take it and leave it as you choose. If escape but with civilisation is your aim have you thought about the Islands? Mallorca has lovely mountain areas and Menorca quiet as a mouse places - they are not all hotels and beaches.
The expat community is of course largely coast or Madrid based. That said with your Spanish you would have little problem integrating into a Spanish community and in my experience in Asturias in the north and Andalucia in the south the locals couldn’t be more friendly. (I certainly find them a lot more friendly than the Brit and German communities on the costa del sol but perhaps that is just me).
In Spain, as in Mexico, fiestas and ferias are important in most parts. I find them not only interesting and entertaining but a great way to get involved. For that I would always look for a working community. The chalet community around a golf course might have its attractions but those places in IMHO lead to isolation.
As one gets older transport can be a concern but in many parts of spain the bus and train network is excellent and cheap. That said I almost bought a house in a mountain village with two buses a day - I got carried away with the scenery.
As expats you might be interested in the internet to stay in touch. It is a little bit more expensive in Spain than in many other countries but is generally available and reliable.
Well now i’m wittering. I thought I would make a reply as no one else had but as you are probable aware there is a wealth of information here in the numerous threads and the members are incredibly helpful. Enjoy.