Help in deciding length of stay and location for Andalucia in the summer

Consider something like this ...

Fly into Madrid for 4 nts
Train to Cordoba for 2 nts
Train to Granada for 2 nts
Train to Ronda for 2 nts
Train to Sevilla for 5 nts
Pick up rental car in Sevilla
Drive to Jerez for 3 nts (day trips to Cadiz and Arcos)
Return rental car to Sevilla
Train to Madrid for 1 nt before departure

Driving in the mountains is slow, drivers are courteous though and parking relatively easy.
June is before the holidays start to hit. July busier. August can be a nightmare.

Since my experience is in low season it is limited. I found driving between the pueblos blancos to be very easy. They are mostly 2-lane highways, with pull-outs at scenic overlooks. The roads are good and well-graded. There were few cars on the road in February. In June traffic might make the driving slower (very difficult to pass on many stretches) but not harder. The scenery was beautiful, so slower isn't so bad. Some of the pueblos are built on very steep hills, with narrow streets and sharp corners, which needs some skill and/or good nerves. I thought the other drivers were courteous and patient.

Andalucia will be hot. Temperatures around 100 are not unusual. Be sure to have hats, sunblock, and drink lots and lots of water, even if you aren't thirsty. It's not humid and you can quickly dehydrate without realizing it.

If you land in Madrid early in the day, consider going straight to Cordoba to begin your trip, then ending it in Madrid. You will want to spend your last night near the airport.

Cadiz is an easy day trip by train from Jerez. I didn't think it was worth more than that. I trained from Cordoba to Sevilla to Jerez. On leaving Jerez, I rented a car to explore the pueblos blancos and kept it until Granada. Ronda was a good base for me, but in the summer it will be crowded, so one of the other towns would probably be better. I would not spend time in Sevilla over and above what you need to see the city, since it is not convenient for day trips.

With a car, you could stop for a night in Antequera on the way to Granada, or along the coast for some beach time. You need a minimum of 2 nights in Granada, to give you a full day to see the Alhambra (be sure to book well in advance). I recommend going the night before to the evening tour of the Nasrid Palaces in addition. Of all the places I visited, Granada was the one I wish I'd stayed for only 2 full days instead of 3, and if you don't see much of Granada except the Alhambra, that's fine too.

I spent 2 nights in Cordoba and enjoyed the evenings there more than any others in Andalucia. Consider adding 1 or 2 nights in Toledo before Madrid. You can also visit as a day tour, but it's said to be much better after the day-trippers leave.

Look at Brad's trip report for more ideas and advice https://community.ricksteves.com/travel-forum/trip-reports/spain-clean-toilets-affordable-lodging

I normally don't weigh in much on itinerary questions because your preferences aren't necessarily my preferences. My technique for deciding length of stay is to first look at guidebooks and decide what I want to see. I separate the available sights into must see, good to see if I have time, and skipable (not the best grammar bet you get the idea). I divide the number of must sees by two and that's how many full days I want in one location. I'll keep the second category information literally in my back pocket in case I find myself with extra time or plan A doesn't work (sight closed for renovation, etc.).

Remember, two nights gives you one full day in a location, three nights equals two full days, etc. Anytime you wake up in one place and go to bed in another should be considered primarily a travel day. Travel days are consumed with packing, checking out, transportation, finding meals, checking in, unpacking/getting settled. I try to keep the legs under four hours on travel days just to keep them workable (sometimes that's not possible).

You should also try to throw in an extra night here and there just for relaxing and adding some flexibility to your schedule.

Driving is very easy. Read my trip report for a lot of thoughts on that (sorry for the pretty unappealing name of the report).

Thanks Chani for mentioning it. :-)

Thanks so much for your input. I'm trying to finalize my plans and now I'm thinking of something quite different:

Cordoba: 5 nights
Granada: 3 nights
Sevilla: 6 nights (Including day trips)
Madrid: 5 nights (visiting friends, so non-negotiable)

I don't like the idea of packing and unpacking more than a few times. I also enjoy really getting to know places rather than just zipping in to see the highlights. I know it will be hot, but traveling in the spring or fall is not an option. I've decided to eliminate the coast, other than day trips because I haven't enjoyed Spanish beaches as much as the ones here in Michigan, so I will save my beach time for the rest of the summer. I've also used public transportation (buses and trains) and find them to be a great way to travel for day trips. I don't think I want to try to rent a car. This will be my 9th trip to Spain and so far, there hasn't been anything wrong, although they have all been completely different. On this trip, my goal is to acquaint my family with Andalucia. I guess I'm posting this to see if anyone thinks this is just a horrible idea and why. Thanks!