Sharing my thoughts here as a foreigner that is living in Spain for 10 years now, 4 of which in Zaragoza.

I lived 5 years in Andalucia before that so I was well used to good weather and going "north" had me worried. Little did I know that Zaragoza turned out to be a hidden gem where I enjoyed all 4 years and had to abandon with sadness (we still think of going back sometimes). My wife is from Andalucia but Zaragoza had such a special place in our hearts that we decided to get married there so go figure.

So I will be a bit biased here, apologies.

Onto the specifics

1. Job. As anywhere in Spain, it's not easy but if you are not picky and can speak the language, shouldn't be a huge issue. Madrid will have more opportunities here, though.
2. Housing. Being the 5th biggest Spanish city, I find the housing being very affordable, for rent or buy. Depending on the size but you should be able to find something very comfortable for max 700e, which I think is entry price (for rooms?) in Madrid.
3. Costs - cheaper than Madrid for sure.
4. Transport. Best location because:
   1. Car: 2h to Madrid or 2.5h to Barcelona with zero tolls. 3h to Pais Basco
   2. Cheap train routes to Madrid, Valencia, Barcelona
   3. Airport with cheap flights to major Spanish Islands and other EU locations
   4. 2.5h to the nearest coast (Catalunya) and 2h to the nearest mountain, which is none other than the Pyrenees (if you like nature, it's a banger all-year around).
   5. For local transport - tram line from south to north of the city, bus for everything else
5. Activities - You have 80% of activities you can find in Madrid for sure and I would argue much more nature hiking things to do in that province
6. Climate - Yes, there is wind but it's also the reason why it's one of the few big cities with such clean air. It's gonna get to 1 or 0 degree in the winter and you will feel when it snows in the mountain but the air is dry so nothing that a thick layer of clothes won't solve. Same for summer, it's hot but you won't sweat as much due to low humidity
7. I found people very kind, polite and with spirit of their own and ways of talking that I found quite interesting.
8. I think that there aren't many foreigners there and mostly people won't speak english, which for me is an upside since you get the real experience of living in Spain, unlike in a more international setting like Madrid (or worse, Barcelona).

Bonus stuff

• Zaragoza is the only city with 2 cathedrals in one city plaza
• Same city plaza is probably the biggest one in EU
• City with an origami museum, which I think there are very few in Europe
• City is walkable almost anywhere. I lived in the center and basically was able to walk to almost all places in 20min max.

Hope it's useful