Madrid and Barcelona in November 2019

Barcelona's average temperatures for November are in the mid 50's and so is Madrid. However, in Madrid temperatures can drop down to the upper 30's at night. Carry a light coat or thick sweater.

Best Neighborhood to stay in Barcelona is Gràcia.

https://www.neverendingvoyage.com/gracia-barcelona-guide/

https://veebrant.com/rooftops-barcelona/

https://www.hotelstheone.com/en/barcelona/restaurants

https://barcelonaeatlocal.com/barcelona-best-rooftop-bars/

For Madrid: The neighborhood I would recommend is Plaza Santa Anna, it's a lovely area within walking distance of everywhere and there is a few really nice bars and places to eat along the square.

http://www.nakedmadrid.com/2019/02/22/rooftop-bars-in-madrid-open-year-round/

https://www.therooftopguide.com/rooftop-bars-in-madrid/tartan-roof.html

For food tours, check link below:

https://devourbarcelonafoodtours.com/

You can see actual, day-by-day historic temperatures on timeanddate.com. I like to check the most recent five years to get a decent idea of the range of conditions I might experience. I've linked to Barcelona's data for November 2018. The temperature in Barcelona should be reasonably pleasant, but I don't think you can expect beach weather.

There's a typo in your original post; it doesn't show how many days you will be in Barcelona. Three nights there would give you just 2-1/2 days. If it's something like that, I'd want to be not too far from the sights I wanted to see or at least extremely close to a Metro stop. The same obviously applies in Madrid.

The tourist offices in Madrid and Barcelona both offered walking tours as of 2016. In my experience they tend to involve somewhat smaller groups of people than the "free" tours--for which you really need to tip generously, since the guides have to turn over 3 or 3.50 euros per person to the company. I especially liked the Barri Gotic tour in Barcelona.

I think in November you'd need an outdoor pool to be heated. You can take a look at possibilities on booking.com. Under the "Property Facilities" filter on the left side of the screen you'll find that one of the options is "swimming pool". You'd need to dig deeper to find out whether the pool is heated.