Yes to all those details from the 70s! I was only on Tenerife at the time, but in a tiny fishing village. Also spent some time on Gomera, got to hear the silbo whistle language in the flesh. Awesome and erie experience. And ate gofio dry with sugar in it. Our friends were very poor. Alas, no train travel until later visits. I like the method you mention at the end. Any particular slow trains you'd recommend?I agree.
My earliest childhood memories are of Spain in the 1970s as we had an elderly relative in the Murcia area. Poverty was still rampant at the time and people were very religious and would sometimes hand us children prayer cards. Outside of a handful of tourist resorts it was still quite rare to see foreign visitors in Spain at that time and we used to attract a lot of attention everywhere we went, and everybody wanted to ask us where we were from and where we were going and people would be very generous in helping us around. My earliest memories are of sleepy little towns with whitewashed houses and dusty streets and stray dogs, with old men in the cafes sipping their cortados, and women dressed mostly in black. Then there were the markets with fresh fruit piled high, a lot of types of fruit we had never seen or heard of before (back then). And the fishmongers with fish so fresh that it had been pulled out of the sea the same morning and that actually looked as if it was still alive.
Many rail lines would get two trains a day. One was the correo which I guess was so called because it also carried mail and typically ran early in the morning. The train was typically a jumble of older cars of different types with no air conditioning, and the tickets very cheap. Then there was the rapido or Talgo which would usually be a modern train with air conditioning and running at a more civilized hour, but the tickets would be much more pricey. There would always be some folks who either genuinely didn't understand the difference or tried their luck and I remember thinking train conductor must be the toughest job around as he was constantly having to argue with people about their tickets.
Once we travelled on dining car which I guess must have been a pre-war Wagons Lits or Pullman car, with lots of intricate art deco woodwork and marquetry and very soft armchair seats. The chef was preparing the food on a charcoal grill. Everything was cooked from scratch with fresh ingredients. It was quite the experience. We were thrilled that such a thing still existed but the Spaniards around us were ashamed of their backward country and apologized profusely.
Since then, the big cities have been modernized beyond recognition and those days seem like a very distant memory, but out in the deep countryside you can sometimes still find places that have stood still in time. The poverty is gone fortunately but the lifestyle hasn't. What I like to do is catch the slow train (they still exist, even if they're not as colorful as they once were) and then just get off at some place that takes my fancy. I've rarely regretted it.